Stainless Steels - Identification Tests

Magnetic, spark, hardness and acid identification tests for austenitic, martensitic and ferritic stainless steels.

Stainless steels can be hard to identify. The different types can be distinguished by methods as

For full table with Sulfuric and Hydrochloric Acid Test - rotate the screen!

Stainless Steels - Identification Tests
AISI Type	Grade	Group	Magnet Test	Spark Test	Hardness Test	Sulfuric Acid Test	Hydrochloric Acid Test
302	Chromium- Nickel	Austenitic	Non- Magnetic	Few forks - short, reddish	>165 Brinell after heated to 1800^oF and water quench	Strong attack - green crystals and dark surface	Rapid reaction - pale blue-green solution
303							Spoiled egg odor - heavy black smudge
303Se							Garlic odor
304						Strong attack - green crystals and dark surface	Fast attack - gas formation
308				Full red without many forks
309
310
316				Few forks - short, reddish		Slow attack - tan surface turns brown	Very slow attack
317						Slow attack - tan surface turns brown
321							Fast attack - gas formation
347							Fast attack - gas formation
410	Chromium	Martensitic	Magnetic	Long white with few forks	> 280 Brinell after heated to 1800^oF and water quench		Rapid reaction - dark green solution
414
416							Spoiled egg odor - heavy black smudge
416Se							Garlic odor
420				Long white-red with burst
431				Long white with few forks
440 A, B, C				Long white-red with burst
430		Ferritic		Long white with few forks	180 - 250 Brinell after heated to 1800^oF and water quench
430F							Spoiled egg odor - heavy black smudge
430FSe							Garlic odor
446				Full red without many forks