Material conversion table (KS-ASTM-DIN-JIS)

Material conversion table (KS-ASTM-DIN-JIS)
1. Gray Iron Castings
2. Spheroidal Graphite (Ductile) Iron Castings
3. Carbon Steel Castings
4. Stainless Steel Castings
5. Bronze Castings
6. Phosphor Bronze Castings 
7. Leaded Tin Bronze Castings
8. Carbon Steel for Machine Structural Use
9. Chromium Molybdenum Steels
10. Rolled Steel for Gerneral Structure
11. Carbon Steel Pipes for Ordinary Pipings
12. Stainless Steel Bars 
13. Stainless Steel Pipes

1. Gray Iron Castings (KS D 4301)
KS	ASTM	DIN	JIS	Tensile Strength (KG-F/mm2)	HB
GC150 (ex-GC15)	A48-CL20	GG15	FC150	19 and above	241 and below
				17 and above	223 and below
				15 and above	212 and below
				13 and above	201 and below
GC200 (ex-GC20)	A48-CL30	GG20	FC200	24 and above	255 and below
				22 and above	235 and below
				20 and above	223 and below
				17 and above	217 and below
GC250 (ex-GC25)	A48-CL35	GG25	FC250	28 and above	269 and below
				26 and above	248 and below
				25 and above	241 and below
				22 and above	229 and below
GC300 (ex-GC30)	A48-CL40	GG30	FC300	31 and above	269 and below
				30 and above	262 and below
				27 and above	248 and below
2. Spheroidal Graphite (Ductile) Iron Castings (KS D 4302)
KS	ASTM	DIN	JIS	Tensile Strength	HB
GCD400 (ex-GCD40)	A536-60-40-18	GGG-40	FCD40	40 and above	201 and below
GCD450 (ex-GCD45)	A536-65-45-12	-	FCD45	45 and above	143~217
GCD500 (ex-GCD50)	-	GGG-50	FCD50	50 and above	170~241
GCD600 (ex-GCD60)	A536-80-55-06	GGG-60	FCD60	60 and above	192~269
3. Carbon Steel Castings (KS D 4101)
KS	ASTM	DIN	JIS	Tensile Strength	HB
SC410 (ex-SC42)	A27-60-30	GS 38	SC42	42 and above	-
SC450 (ex-SC46)	A27-65-35	GS 45	SC46	46 and above	-
SC480 (ex-SC49)	A27-70-36	GS 52	SC49	49 and above	-
4. Stainless Steel Castings (KS D 4103)
KS	ASTM	DIN	JIS	Tensile Strength	HB
SSC1	A743-CA15	G-X12-Cr14	SCS1	55 and above	163 ~ 229
SSC2	A743-CA40	G-X20-Cr14	SCS2	60 and above	170 ~ 235
SSC11	-	X8CrNi-Mo-275	SCS11	60 and above	170 ~ 235
SSC13	A743-CF-8	G-X6Cr-Ni-1809	SCS13	45 and above	183 and below
SSC14	A743-CF8M	G-X6Cr-NiMo-1810	SCS14	45 and above	183 and below
SSC16	A743-CF3M	X2CrNi-Mo-1810	SCS16	40 and above	183 and below
SSC21	A743-CF8C	G-X7Cr-NiNb-1809	SCS21	49 and above	183 and below
5. Bronze Castings (KS D 6010)
KS	ASTM	DIN	JIS	Tensile Strength	HB
BC2	B584-C903	-	BC2	25 and above	-
BC3	B584-C905	G-CuSn10Zn (1705-73)	BC3	25 and above	-
BC6	B584-C836	G-CuSn- 5ZnPb	BC6	20 and above	-
6. Phosphor Bronze Castings (KS D 6010)
KS	ASTM	DIN	JIS	Tensile Strength	HB
PBC2	B505-907	G-CuSn-5ZnPb	PBC2	20 and above	60  and above
7. Leaded Tin Bronze Castings (KS D 6011)
KS	ASTM	DIN	JIS	Tensile Strength	HB
LBC3	B584-937	G-CuPb10Sn	LBC3	-	60  and above
LBC4	B584-938	G-CuPb15Sn	LBC4	-	55  and above
8. Carbon Steel for Machine Structural Use (KS D 3752)
KS	ASTM	DIN	JIS	Tensile Strength	HB
SM30C	A108-1030	-	S30C	48 and above	137 ~ 197
SM34C	A108-1035	-	S35C	52 and above	149 ~ 207
SM45C	A108-1045	-	S45C	58 and above	167 ~ 229
9. Chromium Molybdenum Steels (KS D 3711)
KS	ASTM	DIN	JIS	Tensile Strength	HB
SCM420	-	-	SCM420	95 and above	262 ~ 352
SCM435	A322-4137	34CrMo4 (1.7220)	SCM435	95 and above	269 ~ 331
SCM440	A322-4140	42CrMo4 (1.7225)	SCM440	100 and above	285 ~ 352
10. Rolled Steel for Gerneral Structure (KS D 3503)
KS	ASTM	DIN	JIS	Tensile Strength	HB
SS400 (ex-SS41)	A283 - Gr .D	-	SS41	41 - 52	-
11. Carbon Steel Pipes for Ordinary Pipings (KS D 3507)
KS	ASTM	DIN	JIS	Tensile Strength	HB
SPP	A53 - Gr .F	St - 33 - 1 (1.0033)	SGP1	30 and above	-
12. Stainless Steel Bars (KS D 3706)
KS	ASTM	DIN	JIS	Tensile Strength	HB
STS304	A276-304	X5CrNi-1809 (1.4301)	SUS304	53 and above	187 and below
STS304L	A276-304L	X2CrNi-1809 (1.4306)	SUS304L	49 and above	187 and below
STS316	A276-316	X5CrNi-Mo-1810 (1.4401)	SUS316	53 and above	187 and below
STS316L	A276-316L	X2CrNi-Mo-1810 (1.4401)	SUS316L	49 and above	187 and below
STS321	A276-321	X10CrNi-Ti-1809 (1.4401)	SUS321	53 and above	187 and below
STS329J1	A240-329	-	SUS329J1	60 and above	277 and below
STS403	A276-403	X15Cr13 (1.4024)	SUS403	60 and above	170 and below
STS410	ANSI 410		SUS410
STS416	A582-416	-	SUS413	55 and above	159 and below
STS420J1	A582-420	X20Cr13 (1.401)	SUS420J1	65 and above	192 and below
STS420J2	-	-	SUS420J2	75 and above	217 and below
STS431	A276-431	X22CrNi17 (1.4301)	SUS431	80 and above	229 and below
13. Stainless Steel Pipes (KS D 3576)
KS	ASTM	DIN	JIS	Tensile Strength	HB
STS304TP	A312-TP304	X5CrNi-1809 (1.4301)	SUS304TP	53 and above	-
STS304LTP	A312-TP304L	-	SUS304LTP	49 and above	-
STS316TP	A312-TP316	-	SUS316TP	53 and above	-
STS316LTP	A312-TP316L	-	SUS316LTP	49 and above	-

 
  Source: http://www.itraders.biz

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Knowledge About Steel

STEEL AS Engineering MATERIAL

Steel is the backbone of all Industries and the basic ingredient for growth and development of a country. Traditionally, the fortunes of the steel industry have been linked to the economic cycle of the country. Per capita consumption of steel speaks volumes about the relative position of the country on the development frontier. In India the per capita consumption of steel stands very low (38 kg) in compare to world average per capita consumption of steel (170 kg), where total production of steel is about 1200 MT. Moreover, steel is completely recyclable and thus environment friendly. Hence a large potential exists in furthering the usage of steel in various segments of industry.

If anyone metal is to be named, which has maximum impact on mankind, it is steel. It is the most important metal today, which enjoys about 95% of total metal output globally. A compound basically made of iron and carbon and some other elements is called Steel. Thus steels are alloys of iron (Fe) and carbon (C). Its mechanical properties (and the electrical or magnetic properties) are influenced by the addition of various elements (Cr,Mn,Ni,Si etc). Carbon is the element that modify the allotropic (crystal structure) changes that iron displays during heating and cooling. These structural changes occur during processing or manufacture of the steel. Different types of steel are produced for particular applications and are manufactured within precise composition limits and processing conditions in order to provide the required microstructure, properties and functionality.Steel as an Engineering Material is of great interest to Architects, Civil and Structural engineers, Designers, Consultants, Metallurgists and Project owners.

Like all metals iron (Pig Iron) is made from iron ore, coke and limestone in blast furnace or by direct reduction processes. Production of steel from pig iron involves processes like steel making, primary and secondary steelmaking, casting and hot rolling. The carbon content of steels is up to 2.0%. The microstructure and atomic structure varies with carbon content and temperature. A wide range of strength levels, from 120 to over 3000 mpa can be obtained with the help of carbon and alloying elements by mechanical working and heat treatment.



Steel enjoys the widest range of applications among the materials known to mankind due to different mechanical properties and product forms. It touches everybody’s life everyday everywhere.

Segments	Typical Applications
Construction	Industrial, Hospital, Institutional Buildings, Exhibition Halls, Stadiums, Railway and Bus stations, offshore structures
Agriculture & Rural areas	Machinery, Storage tanks, Grain bins, Bullock Carts, Meeting Halls
House Hold	Buckets, Scissors, Kitchen cabins, Ovens, white goods, utensils, furniture
Infrastructures	Bridges, Flyovers, Foot Bridges, Culverts and RCC Structures
Oil, Gas & Power	Wells, Platforms and items related to power
Transport	Railways, Buses, Trucks, Luxury Coaches, Cars, two-wheelers, bicycles
Electrical & Electronics	Transformer core, Motors, Transmission Towers

Grades of Steel:

Mild Steel is the commonest grade of steel containing less than 0.25% Carbon. Medium Carbon Steel has carbon content 0.25% to 0.45% and used as input material in the engineering industries. High Carbon Steel refers to the harder steel with carbon content 0.45% to 0.90% and is used to make precision tools and instruments. Alloy Steels/Special Steels including Stainless Steel are produced by adding alloying elements like Mn,W,Ni etc. Stainless Steel contains Cr and Ni with proper proportions. Weathering steels are used for atomoshpheric corrosion resistance purpose.

Finished Steel is divided into two categories like Non Flat products (bars, rods, angles, joist, channels & railways materials) and Flat (plates, hot rolled coils, cold rolled coils/sheets, galvanized plated, galvanized corrugated coils/sheets, tin plates and electrical sheets.)

Hot metal is processed further to get better quality, strength and specific application through different routes like:

• Basic Oxygen Furnace Steel making (BOF) : The purpose is to refine the hot metal produced in the blast furnace, which may be subsequently refined in the secondary steelmaking shop. The main functions are to remove carbon & phosphorus from the hot metal, and to optimize the steel temperature so that any further treatments prior to casting can be performed with minimal reheating or cooling of the steel. 
• Electric Arc Furnace (EAF) : Recycled steel scrap is melted and converted into high quality steel by using high-power electric arcs. The main task is to convert the solid raw materials to liquid crude steel and then refine further in subsequent secondary steelmaking processes. 
• Secondary Steelmaking: It is a critical step in the steel production process between the primary processes (BOF or EAF) and casting. Some elements are added and some have to be removed during secondary steelmaking in order to fine-tune the composition of the steel to meet the specification. . After secondary steelmaking, the ladle of liquid steel is taken, at the required composition, quality, cleanness, time, temperature and at least cost to the casting process.
• Continuous Casting: The molten steel is continuously cast through a tundish into a water-cooled copper mould causing a thin shell to solidify. The solidified shell continues to thicken until the strand is fully solidified. Finally, the strand is cut into desired lengths. Depending on final application cast dimensions may be slab for flat products (plate, strip etc), blooms for structural sections (beams, channels etc) and billets for long products (wire). Hot Rolling: It is the most efficient process of primary forming used for the mass production of steel. The principal effects of hot rolling are the elimination of the cast ingot structure defects and obtaining the required shape, dimensions and surface quality of a product. This makes both semi-finished and finished products. Semi-finished hot-rolled steel products are the starting materials for further hot metal forming processes (flat, long products, seamless tubes, wheels, rings, bars etc) and cold rolling.
  Cold Forming: Hot-rolled products are often subjected to further processing like cold rolling, forming, machining and joining, in order to get desired strength and properties for specific applications.

 Mechanical Properties:

Like all metallic materials specific steels are having specific mechanical properties. Steel properties can be divided into two groups:
a.         Structure insensitive
b.         Structure sensitive
Principal structure insensitive properties are elastic modulus, density and some chemical, electrical and thermal characteristics. The structure sensitive properties are wholly dependent upon the past history – whether hot rolled or cold rolled, whether heat treated and if so how. The most important structure sensitive properties are yield strength, tensile strength, ductility fractures toughness, fatigue characteristics, etc.

Elastic Moduli : These are commonly defined in terms of the relationship between stress s,  and strain €, in that region where the curve is linear.

The most frequently used is the modulus in tension :
Young’s Modulus ‘E’ = Tension Stress / Tension Strain
Also used is the Shear Modulus ‘G’ = Shear Stress / Shear Strain
The units of the modulus are the same as those of stress i.e. N/mm2 (ksi). Since the modulus is a structure insensitive property, the normal design value E = 205 kN/mm2 may be used for all steels, regardless of composition, origin, prior history etc.

Yield Strength: Yield point is the transition between reversible and permanent deformation when the material is stressed till yield point stress -strain curve is linear and at the yield point some non-uniform deformation take place as shown in figure. It is in fact that transition from elastic to plastic behavior yield strength is affected by composition and grain size. Some steels do not exhibit a clearly defined and the stress strain as a smooth continuous curve. In such cases, a stress which corresponds to a definite amount of permanent extension (equivalent 2%) is taken as yield stress and is called proof stress.

Tensile Strength: This occurs when material starts to deform locally, a waist or neck is produced at which facture is eventually occur. This is a maximum stress subject to the material before the necking starts. In figure the stress level is shown as (E). 

Ductility: The reduction in area and the total elongation at fracture are used as measure of ductility.

Fracture Toughness: Fracture toughness is a measurement of ductile to brittle transition of material. Brittle fracture always starts at a discontinuity such as a notch an incompletely fused weld or a design discontinuity such as a hole or a corner where stress is locally increased. For a steel of given position, the onset of brittle rather than ductile, behavior is affected both by temperature and rate of loading. The chemical composition of steel and the grain size affect the ductile brittle transition. Practically notch impact test is done in case of steel to assess its relative toughness. The fracture toughness is generally measure in terms of ductile-brittle transition temperature.

Fatigue: Failure by fatigue occurs as a result of reversing or fluctuating stress like brittle fracture, always starts from a stress raiser / discontinuity. Fatigue property has to be taken into consideration while designing a machine, bridge, industrial structure etc.

Specifications: Different classes of steels are available meeting desired requirement of end applications, which are clearly defined in respective specifications. Carbon Steel Fy=240 to 250 MPa is widely used in construction Industry, Micro Alloy Steel with Fy 350MPA and above is also being used for all type of construction and all type of equipment manufacturing, where Fy is yield strength of steel

Joining of Steel: Mostly can be done easily by welding,rivetting and bolting.

Compiled by Ajay Prasad :: ajp_ds@yahoo.com

Source:http://www.structural-world.org

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Corrosion Resisting steel - Grade 3CR12

3CR12 Technical Data

Summary

3CR12 is a chromium containing corrosion resisting steel developed as an alternative material of construction where the mechanical properties, corrosion resistance and fabrication requirements of other materials such as mild steel, galvanised or aluminised steel, aluminium or pre-painted steels are unsuited.

Originally 3CR12 was not included in any international specifications. However, a 12 per cent chromium steel developed from 3CR12 has been designated DIN type 1,4003 and ASTM/ASME 41003. The former has been incorporated into two Euronorm Standards viz. EN 10088 and EN 10028, 3CR12 conforms to the requirements of the above specifications and is multi certifiable to 3CR12, 1.4003 and 41003, due to its inclusion in the above specifications. 3CR12 vessels and tanks can be designed in accordance to BS5500, ASME, AD Merkblatter codes and the Euronorm design specification currently in preparation.

Although 3CR12 is recognised as the World's most specified 12% Chromium utility steel, it is by no means universal and should not be substituted for higher grades of stainless steel unless detailed corrosion testing has been carried out. Columbus Stainless can be consulted for advice in this regard.

3CR12 was designed as a corrosion resisting steel and, as such, will exhibit staining when exposed to aggressive atmospheric conditions. In applications where aesthetic appearance is important, it is recommended that 3CR12 is painted, or a higher grade should be used.

A long term atmospheric corrosion programme conducted over 20 years bv the CSIR has shown 3CR12 to have very good atmospheric corrosion resistance, Stainless steels, with their higher chromium contents, exhibited very low corrosion rates. Because of 3CR12's inherent corrosion resistance, it has been used successfully under wet sliding abrasion conditions such as found in the mining and bulk handling industries. In the case of mild or low alloy steels the presence of moisture in the solids being transported aggravates deterioration of the working surfaces. Not only does the surface rust wear away rapidly exposing bare metal to further corrosion, but corrosion of the working surface leads to 'hang-up' and interrupted flow. 3CR12 resists the corrosive attack and thereby improves flow and reliability, while extending the life of the solids handling equipment.

Although 3CR12 performs very well in corrosion-abrasion applications, no real benefit can be gained by using it under dry abrasion conditions. 3CR12 is not especially suitable under conditions of impact abrasion. (See: A Guide to the Use of 3CR12 in Corrosion Abrasion Applications).

3CR12 has been extensively used in aqueous environments, and has been successful in many applications involving exposure and/or immersion. It is important when using 3CR12 in aqueous environments that the decision be based on a thorough water quality analysis and microbial count. (See: A Guide to the use of 3CR12 in Water).

3CR12 is designed with ease of fabrication in mind and its composition and properties result in good forming, drawing, blanking and punching characteristics. The steel is easily welded by any of the recognised welding processes and should be post weld pickled/cleaned and passivated.

3CR12 has been included in SABS 0162 Part 4 - Code of Practice for the Structural Use of Steel. When replacing carbon steel with 3CR12, it is necessary to redesign mild and constructional steel components using the mechanical and corrosion resisting properties of 3CR12 in order to gain full advantage of potential material and fabrication savings.

This document covers black (hot rolled and annealed) 3CR12 as well as pickled (No1 and 2B) material, 3CR12 is available in the following finishes HRA, No 1, 2D and 2B, Whereas the latter three finishes can be used for all suitable 3CR12 applications, the HRA finish should only be used in applications where wet sliding abrasion occurs. It should never be used in immersion conditions The mechanical properties of the HRA material are similar to those of the No 1 finish material. A long term atmospheric programme conducted over 20 years by the CSIR has shown 3CR12 to have very good atmospheric corrosion resistance.

 

Properties of 3CR12
  Chemical Composition
 

%C	%Ni	%Mn	%Si	%P	%S	%Cr	Other
0.03   Max	1.5   Max	1.5   Max	1.0   Max	0.03   Max	0.03  Max	11.0 - 12,0	Ti  0.6 Max

  1. Mechanical Properties
 

Ultimate Tensile Strength (Transverse)	450 MPa Min
0.2% Offset Proof Strength   (Transverse)	< 6,0 mm thick  -  320 MPa Min  > 6,0 mm thick  -  280 MPa Min
Elongation (in 50mm)	< 6,0 mm thick  =  20% Min
	> 6,0 mm thick  =  18% Min
Hardness	< 12.0 mm thick  -  220 Brinell Max
	> 12.0 mm thick  -  250 Brinell Max
Charpy Impact (Ambient temperature)	35 J/cm2 Min

2. Fatigue

Extensive testing has shown that 3CR12 behaves in a similar manner to constructional steels such as BS4360 Grade 43A in terms of fatigue. Accepted procedures when desgning for fatigue loaded structures should be followed. BSBS7068 can be used.
 
3. Physical Properties

At Room Temperature.
Density		7 740 kg/m3
Elastic Modulus (Tension)		200 GPa
Specific Heat Capacity		478 J/kg K
Thermal Conductivity	@ 100oC	30.5 W/m K
	@  500oC	40.0 W/m K
Electrical Resistivity		66 x 10-9Wm
Co-efficient of	0-100oC	11,1 mm/mK
thermal expansion	0-300oC	11.7 mm/mK
	0-700oC	12.3 mm/mK
Melting Range		1'430 - 1'510oC
Relative Permeability		Ferromagnetic

4. Corrosion Resistance

3CR12, with chromium as its major alloying element, is not intended as a material for use in contact with process solutions such as acids, salts, etc.  It is more suited to applications involving ancilliary equipment on process plants such as cable racking, stairways, flooring, handrailing, etc.  3CR12 is a "corrosion resistant" rather than "stainless" steel and as such, will tend to form a light, surface rust or discolouration when exposed to aggressive environments.  This patina is superficial and does not affect the mechanical properties of the steel.
Should aesthetic or hygienic qualities be of prime importance, stainless steels rather than 3CR12 should be considered, although 3CR12 can be successfully painted with a number of paint systems.

Aqueous Corrosion

It is recommended that consultations be held with Columbus Stainless technical staff on the use of 3CR12 in water.
At the design stage, efforts must be made to avoid crevices, sedimentation, stagnancy, high operating temperatures etc., as these facts will have a negative impact on the performance of the steel.
3CR12 is not recommended for use in hot water systems unless detailed testing has previously been carried out.

Atmospheric Corrosion

A long term atmospheric corrosion programme conducted over 10 years by the CSIR has shown 3CR12 to have very good atmospheric corrosion resistance.  Data on the performance of various materials at different test sites is available from VRN Technical staff.

5.  Fabrication of 3CR12

Note:  A detailed 3CR12 fabrication guideline is available from Columbus Stainless.

Cutting

For general fabrication requirements, the most effective cutting methods are:                       
                                                         

Abrasive disc	- use dedicated discs
	- avoid overheating
	- vitrified or resinoid aluminium oxide discs  recommended
Plasma	- oxygen-free nitrogen is the most economical primary cutting gas.    (Other gasses can be used)
	- heat discolouration must be removed prior to use in a corrosive   environment
Guillotine	- use well sharpened and correctly alligned and set blades to avoid sheared breaks and rollover.
	- capacity of guillotine (rated in terms of mild steel thickness) must be   downrated by 40% of 3CR12.

Forming

It is important to note that due to the higher proof strength of 3CR12, more power is required for most forming operations, than would be needed for mild steel.
When bending 3CR12 it is important to maintain a minimum inner bend radius equal to twice the material thickness.  Reverse bending at ambient temperatures is not recommended - the bend area should be preheated to +- 150^oC .  Edge cracks can be avoided by placing the cut face on the outside radius of the bend and the sheared face on the inside.  This type of cracking can also be prevented by grinding the outside radius point of bending into a rounded profile, thus eliminating the natural stress concentration point.

Welding

Manual metal arc, metal inert gas and tungsten inert gas are the common procedures used.  All welding procedures must ensure that heat inputs are kept to a minimum.  Down-hand welding is the preferred welding position and bead runs rather than weaving should be used.  Austenitic stainless steel filler metals such as AWS ER 309L, 308L, or 316L should be used.
In order to ensure adequate corrosion resistance in weld zones, it is necessary to remove all heat tint by pickling or by some mechanical means and passivating with a cold 10% nitric acid solution after cleaning.  Thorough washing with clean, cold water pickling and passivating is essential.

Machining

In the annealed condition, 3CR12 has machining characteristics similar to AISI 430 i.e. a machinability rating of 60.  The reduced extent of work-hardening compared to austenitic stainless steel eliminates the need for special cutting tools and lubricants.  Slow speeds and heavy feeds with sufficient emulsion lubricant will prevent machining problems.

Fastening

Where 3CR12 sections are to be bolted, stainless feel fasteners such as type 304 or 431 are preferred.  If bolted structures are to be used in humid or wet environments, it is strongly recommended that compressible, non-absorbant gaskets such as rubber be used.

Thermal Processing

Annealing
3CR12 is supplied in the annealed condition, its softest and most ductile state.  After severe cold forming operations or after hot forming operations above 750^oC, annealing may be required.  Annealing is carried out at 700-750^oC  followed by air cooling.
Soaking times are 12 hours per 25mm section.

Stress Relieving
Stress relieving is not recommended for 3CR12.  If it is essential, temperatures of not more than 450^oC  should be employed.

Hot Forming
Any hot forming should preferably be conducted at temperatures below 750^oC. The recommended temperature range is between 600^oC and 700^oC and annealing should be performed after forming.

Source: www.fanagalo.co.za

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Properties of Stainless Steel - Grade 316, 316L

SX 316 / 316L Technical Data

 Summary

SX 316 is an improved version of SX 304, with the addition of molybdenum and a slightly higher nickel content. The resultant composition of SX 316 gives the steel much increased corrosion resistance in many aggressive environments.  The molybdenum makes the steel more resistant to pitting and crevice corrosion in chloride-contaminated media, sea water and acetic acid vapours.   The lower rate of general corrosion in mildly corrosive environments gives the steel good atmospheric corrosion resistance in polluted marine atmospheres.
SX 316 offers higher strength and better creep resistance at higher temperatures than SX 304.  SX 316 also possesses excellent mechanical and corrosion properties at sub-zero temperatures.  When there is a danger of corrosion in the heat-affected zones of weldments, the low-carbon variety SX 316L should be used.  SX 316 Ti, the titanium-stabilised version, is used for its resistance to sensitization during prolonged exposure in the 550^oC-800^oC temperature range.

 

Typical Applications

Because of its superior corrosion and oxidation resistance, good mechanical properties and fabricability, SX 316 has applications in many sectors of industry.  Some of these include:
Tanks and storage vessels for corrosive liquids.
Specialised process equipment in the chemical, food, paper, mining, pharmaceutical and petroleum industries.
Architectural applications in highly corrosive environments.

Chemical Composition (ASTM A 240)
 

	C	Mn	P	S	Si	Cr	Ni	Mo	Ti
SX316 SX316L SX316Ti	0.08 max 0.03 max 0.08 max	2.0 max	0.045 max	0.030 max	1.0 max	16.0 to 18.0	10.0 to 14.0	2.00 to 3.00	- 0.5 max 5X%C

Typical properties in the annealed condition
The properties quoted in this publication are typical of mill products and unless indicated must not be regarded as guaranteed minimum values for specification purposes.

1. Mechanical properties at room temperature
 

	SX316		SX316L		SX316Ti
	Typical	Minimum	Typical	Minimum	Typical	Minimum
Tensile Strength, MPa	580	515	570	485	600	515
Proof Stress (0.2 % offset), MPa	310	205	300	170	320	205
Elongation (Percent in L = 5.65 So)	55	40	60	40	50	40
Hardness (Brinell)	165	-	165	-	165	-
Erichsen Cup Test Value mm	8 - 10	-	10 - 11	-	-	-
Endurance (fatigue) limit, MPa	260	-	260	-	260	-

2. Properties at elevated temperatures
The values given refer to SX 316 and SX 316 Ti only as strength values for SX 316L fall rapidly above 425^oC.

Short Time Elevated Temperature Tensile Strength

Temperature, C	600	700	800	900	1000
Strength, MPa	460	320	190	120	70

Creep data
Stress for a creep rate of 1% in 10 000 h

Temperature, oC	550	600	650	700	800
Stress, MPa	160	120	90	60	20

Recommended Maximum Service Temperature
(Oxidising conditions)

Continuous Service            925^oC
Intermittent Service             870^oC

3. Properties at Sub-Zero Temperatures
( SX 316 )
 

Temperature	oC	-78	-161	-196
Proof Strength (0.2% Offset)	MPa	400	460	580
Tensile Strength	MPa	820	1150	1300
Impact Strength (Charpy V-Notch)	J	180	165	155

4. Corrosion Resistance

4.1    Aqueous
         For specific conditions, consult VRN technical staff.  As a rough guide, the following examples are given
         for pure acid-water mixtures.
 

TemperatureoC	20	80
Concentration, (-% by mass)	10       20       40       60       80       100	10       20       40       60       80       100
Sulphuric Acid	0          1         2         2         1          0	2          2         2        2         2         2
Nitric Acid	0          0         0         0         0          1	0          0         0        0         1         2
Phosphoric Acid	0          0         0         0         1          2	0          0         0        0         1         2
Formic Acid	0          0         0         1         1          0	0          0         1        1         1         0

 Key:         0 = resistant    -    corrosion rate less than 100 mm/year
                 1 = partly resistant    -    corrosion rate 100 m to 1000 mm/year
                2 = non resistant    - corrosion rate more than 1000 mm/year
 

4.2    Atmospheric
          The performance of SX 316 compared with other metals in various environments is shown in the
          following table.  Corrosion rate is based on a 5 year exposure.
 

Environment	Corrosion Rate (mm/year)
	SX 316	Aluminium-3S	Mild Steel
Rural	0.0025	0.025	5.8
Marine	0.0076	0.432	34.0
Marine-Industrial	0.0051	0.686	46.2

Note:  For corrosion resistance of SX 316 relative to other types, see the section in Comparative Data.

4.3    Thermal Processing

4.3.1 Annealing. Heat from 1 010^oC to 1 120^oC and cool rapidly in air or water.  The best corrosion
          resistance is obtained when the final annealing temperature is above 1 070^oC.

4.3.2 Stress relieving.  Heat from 200 - 400^oC and air cool.

4.3.3 Hot working
          Initial forging and pressing:                                    1150  - 1200^oC
          Finishing temperature:                                            above 900^oC
          For upsetting operations, forgings
          should be finished between:                                   930 and 980^oC
          All hot working operations should be followed by annealing.

Note:  Soaking times to ensure uniformity of temperature are up to 12  times that required for the same thickness of mild steel.

Cold Working

SX 316 / 316L, being extremely tough and ductile, can be readily fabricated by cold working. Typical operations include bending, forming, deep drawing and upsetting.

Source: www.fanagalo.co.za

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