SUS 321

HuaNickel SUS 321 stainless steel is a titanium stable grade that is typically used in the 1000-1600°F temperature range. For operating temperatures up to 1600°F, a stable treatment of 1550-1650°F, air cooling, can be used to provide optimal resistance to intergranular corrosion and polysulfuric acid stress corrosion cracking. HuaNickel SUS 321 stainless steel is easily welded by all common methods, including water arcing. The appropriate weld fillers are AWS ER347 bare wire and E347 overlay electrodes. The machinability of SUS 321 stainless steel is similar to that of 304 stainless steel. Compared to AISI B1112, it has a machinability rate of 45%.

SUS 321Chemical composition：

	Cr	Ni	Mo	Ti	C	Mn	Si	P	N	Fe
Min	17	9	–	5x(C+N)	–	–	0.25	–	–	Bal
Max	19	12	0.75	0.7	0.08	2	1	0.045	0.1

SUS 321Physical properties：

Density	Melting point
0.286 lb/in³	2550 – 2600°F

SUS 321Mechanical properties：

Average high-temperature tensile properties

Temperature, °F	68	400	800	1000	1200	1350	1500
Ultimate tensile strength, ksi	93.3	73.6	69.5	63.5	52.3	39.3	26.4
0.2% yield strength, ksi	36.5	36.6	29.7	27.4	24.5	22.8	18.6

The average stress at break

Temperature，°F	1050	1100	1150	1200	1250	1300	1350	1400	1450	1500
1000hour，ksi	34	29	22	17.5	13	11.5	7.5	6.5	5	4
10000hour，ksi	27.5	22	16	12.5	9	7	5	4	3	2.5
100000hour，ksi	21.5	15	10.5	7.5	5	4	3.5	2.5	2.3	2

SUS 321Stainless steel characteristics：

Oxidation resistance 1600°F

Prevents intergranular corrosion in the weld heat-affected zone (HAZ).

Resistant to polysulfuric acid stress corrosion cracking

SUS 321Uses of stainless steel：

Aircraft piston engine manifolds

Expansion joints, thermal oxidants

Refinery equipment

High-temperature chemical process equipment

Relevant standards：

ASTM: A 240, A 276, A 312, A 479 GE: B50T1181

ASME: SA-240, SA-276, SA-312, SA-479