ODIL Type 304 is a variation of the basic 18-8 grade, Type 302, with a higher chromium and lower carbon content. Lower carbon minimizes chromium carbide precipitation due to welding and its susceptibility to intergranular corrosion. In many instances, it can be used in the ”as-welded“ condition, while Type 302 must be annealed in order to retain adequate corrosion resistance.

Type 304L is an extra low-carbon variation of Type 304 with a 0.03% maximum carbon content that eliminates carbide precipitation due to welding. As a result, this alloy can be used in the ”as-welded“ condition, even in severe corrosive conditions. It often eliminates the necessity of annealing weldments except for applications specifying stress relief. It has slightly lower mechanical properties than Type 304.

	Type 304 %	Type 304L %
Carbon	0.08 max.	0.03 max.
Manganese	2.00 max.	2.00 max.
Phosphorus	0.045 max.	0.045 max.
Sulfur	0.030 max.	0.030 max.
Silicon	0.75 max.	0.75 max.
Chromium	18.00-20.00	18.0-20.0
Nickel	8.00-12.00	8.0-12.0
Nitrogen	0.10 max.	0.10 max.
Iron	Balance	Balance

Typical uses include architectural mouldings and trim, kitchen equipment, welded components of chemical, textile, paper, pharmaceutical and chemical industry processing equipment.

Typical Room Temperature Mechanical Properties

	UTS ksi (MPa)	2% YS ksi (MPa)	Elongation %in 2" (50.8 mm)	Hardness Rockwell C
Type 304L	85 (586)	35 (241)	55	B80
Type 304	90 (621)	42 (290)	55	B82

Type 305 is an austenitic chromiumnickel stainless steel that can be spun and deep drawn more easily due to an increased nickel content that decreases work hardening. It is nonmagnetic and cannot be hardened by heat treatment.

	In Percentage (%)
Carbon	0.12 max.
Manganese	2.00 max.
Phosphorus	0.045 max.
Sulfur	0.030 max.
Silicon	1.00 max.
Chromium	17.00 - 19.00
Nickel	10.00 - 13.00
Iron	Balance

Typical uses include appliances, kitchen utensils, tank covers and other deep drawn parts.

Typical Mechanical Properties*

Condition	UTS ksi (MPa)	2% YS ksi (MPa)	Elongation %in 2" (50.8 mm)	Hardness Rockwell C	Impact Strength Izod V-Notch ft-lbs (J)
Annealed	85 (586)	38 (262)	50	B80	110 (140)

Types 309 and 309S are austenitic chromium-nickel stainless steels that provide excellent corrosion resistance and heat resistance plus good strength at room and elevated temperatures. Type 309S is identical to Type 309 except for a lower carbon content that minimizes carbide precipitation and improves weldability. They are essentially nonmagnetic as annealed and become slightly magnetic when cold worked.

	Type 309 %	Type 309S %
Carbon	0.20 max.	0.08 max.
Manganese	2.00 max.	2.00 max.
Phosphorus	0.045 max.	0.045 max.
Sulfur	0.030 max.	0.03 max.
Silicon	0.75 max.	0.75 max.
Chromium	22.00 - 24.00	22.00 - 24.00
Nickel	12.00 - 15.00	12.00 - 15.00
Iron	Balance	Balance

Typical uses include furnace parts, heating elements, aircraft and jet engine parts, heat exchangers, carburizingannealing boxes, sulfite liquor handling equipment, kiln liners, boiler baffles, refinery and chemical processing equipment, and auto exhaust parts.

Typical Mechanical Properties*

Condition	UTS ksi (MPa)	0.2% YS ksi (MPa)	Elongation %in 2" (50.8 mm)	Hardness Rockwell C	Impact Strength Izod V-Notch ft-lbs (J)
Annealed	90 (621)	45 (310)	45	B85	110 (140)

Type 316 is an austenitic chromiumnickel stainless steel containing molybdenum. This addition increases general corrosion resistance, improves resistance to pitting from chloride ion solutions, and provides increased strength at elevated temperatures. Properties are similar to those of Type 304 except that this alloy is somewhat stronger at elevated temperatures. Corrosion resistance is improved, particularly against sulfuric, hydrochloric, acetic, formic and tartaric acids; acid sulfates and alkaline chlorides. Type 316L is an extra-low carbon version of Type 316 that minimizes harmful carbide precipitation due to welding.

	Type 316 %	Type 316L %
Carbon	0.08 max.	0.03 max.
Manganese	2.00 max.	2.00 max.
Phosphorus	0.045 max.	0.045 max.
Sulfur	0.030 max.	0.03 max.
Silicon	0.75 max.	0.75 max.
Chromium	16.00 - 18.00	16.00 - 18.00
Nickel	10.00 - 14.00	10.00 - 14.00
Molybdenum	2.00 - 3.00	2.00 - 3.00
Nitrogen	0.10 max.	0.10 max.
Iron	Balance	Balance

Typical uses include exhaust manifolds, furnace parts, heat exchangers, jet engine parts, pharmaceutical and photographic equipment, valve and pump trim, chemical equipment, digesters, tanks, evaporators, pulp, paper and textile processing equipment, parts exposed to marine atmospheres and tubing. Type 316L is used extensively for weldments where its immunity to carbide precipitation due to welding assures optimum corrosion resistance.

Typical Room Temperature Properties

	UTS ksi (MPa)	0.2% YS ksi (MPa)	Elongation %in 2" (50.8 mm)	Hardness Rockwell C
Type 316	84 (579)	42 (290)	50	B79
Type 316L	81 (558)	42 (290)	50	B79

Type 321 is a stabilized austenitic stainless steel similar to Type 304 but with a titanium addition of at least five times the carbon content. This titanium addition reduces or prevents carbide precipitation during welding and in 800 - 1500°F (427 - 816°C) service. It also improves the elevated temperature properties of the alloy.

Type 321 provides excellent resistance to oxidation and corrosion and possesses good creep strength.

Applications include annealing covers, high-temperature tempering equipment, diesel and heavy duty automotive exhaust systems, firewalls, stack liners, boiler casings, welded pressure vessels, jet aircraft components, radiant superheaters, bellows and oil refinery equipment.

	In Percentage (%)
Carbon	0.08 max.
Manganese	2.00 max.
Phosphorus	0.045 max.
Sulfur	0.030 max.
Silicon	0.75 max.
Chromium	17.00-19.00
Nickel	9.00-12.00
Titanium	5 x (C + N) min., 0.70 max.
Nitrogen	0.10 max.
Iron	Balance

321SS is used primarily in applications involving continuous and intermittent service temperatures within the carbide precipitation range of 800 - 1500°F (427 - 816°C).

Typical Room Temperature Properties

UTS ksi (MPa)	0.2% YS ksi (MPa)	Elongation %in 2" (50.8 mm)	Hardness Rockwell
90 (621)	0 (276)	45	B80