TAIWAN TOKKIN CO., LTD.

Material:

Elements Influence

Elements	Carbide generation function	Quenching influence	Tempering influence	Ferrite influence	Main Effect
Si	Reverse function (graphite)	Quenching Improved	Tempering resistance is strong. Maintain the hardness by solution treatment	Harden or lower toughness P>Si>Mn	Deoxidizer Increase the resistance of oxidization and corrosion Increase the strength of low alloy steel Magnetic steel sheet (Silicon steel 0.5-6.0% Si)
Mn	Strong Cr>Mn>Fe	High Cr>Mn>Ni	Tempering resistance is weak Ｃr/Si>Ｍn>Ｎi	Reinforce ferrite after solution treatment and Increase toughness Mo>Mn>Ni	Deoxidizer Avoid brittleness caused by S Improve quenching performance Abrasion-and-Impact resistance steel (hard field steel with high Mn 10-14%Mn) Stainless steel instead of Ni (SUS201,202)
P	Weak	Increased by quenching crack	Increase tempering resistance	Harden magnificently after solution treatment, but brittleness is also big.	The reason of low temperature and tempering brittleness; Improve fluidity of iron and steel; Increase low carbon steel strength and the corrosion resistance; Increase mechanical ability of free cutting steel
S		No influence to quenching crack			Might cause white or red heat brittleness; Sulfur free cutting steel (0.1-0.3% S); Create no metal inclusion
Cr	Very strong W>Cr>Mn	big	Avoid softness	Harden slightly	Increase the resistance rust and oxidization (Stainless steel) Increase high temperature strength (heat resistant steel) Abrasion resistance is increased by high C (bearing steel) Improve quenching performance
Ni	Fe>Ni (graphite)	Quite high, remain Austenite for high car-bon	without tempering resistant	Increase toughness and hardness	Improve the toughness from tempering. Increase the low temperature toughness of carbon steel Add Austenite stainless steel into high Cr-Fe alloy High Ni-Fe alloy (permalloy 40-80% Ni)
Cu		raise slightly, half of Ni	Without tempering resistant (precipitation hardening at 450-600℃)		Increase the corrosion resistance Increase the strength of low alloy steel The red heat brittleness will happen if Cu is contained too much Aging Occurs
W	Very strong	small quantity but big	Tempering resistant big Secondary hardening big	Aging hardening be big when harden magnificently	Increase high temperature strength magnificently (high speed steel) Supply abrasion resistance by special carbide Magnetic steel (1-10% W)
Mo	Strong Mo>Cr	big (Mo>Cr when solution)	Avoid tempering brittleness. Tempering resistance big. Secondary hardening big	Increase toughness	Increase the growth temperature of Austenite grain Increase hot creep limitation, red heat and room temperature strength Avoid tempering brittleness Increase corrosion resistance Increase quenching
V	Strong Ti / Nb >V>Mn	Very big when do solution	Tempering resistance big. Secondary hardening is the maximum	Be slightly harden	Austenite grain will be thinner and avoid grain growth. Increase high temperature strength Carbon carbide be thinner Earn non-aging
Co	Same as Fe	Reverse affect (decrease quenching)	Keep hardness after solution	Be harden after solution	Increase heat strength by Ferrite hardness Magnetic steel (2-40% Co) ( High speed steel with hard alloy)
Al	Fe > Al (graphite)	Small		Be harden after solution	Strong deoxidizer Grain be thinner Increase heat resistance Nitride steel Precipitation-hardened alloy mixture(sus631)
Ti	Strongest	Big in solution	2nd hardening	Be harden after solution Fe-Ti alloy have aging hardening	Deoxidizer can avoid brittleness and strain Stable the carbonation and avoid quenching hardening Increase creep resistance Avoid grain boundary corrosion of Austenite stainless (SUS321)

[ Notes ] Not to influence with back face in the hardness test of indenter impression