W.-Nr. 1.4109 to EN 10 088-2 (DIN/EN) X70CrMo15 Cold rolled annealed and pickled stainless steel strips Material

Designations

Description

This high-carbon high-chromium martensitic stainless steel is designed to provide stainless properties with excellent hardness.

It has moderate corrosion resistance as-annealed which has permitted its use in mild environments.

In some respects it behaves similarly to tool steels.

Type 440A attains a hardness of Rockwell C 56 and maximum toughness when heat treated.

Type 440A has been used for pivot pins, dental and surgical instruments, cutlery, valve parts, etc.

Chemistry data ( in weight % )

Delivery state

Annealed

Heat treatment

Annealing

For maximum softness, this steel should be heated uniformly to 1550/1600ºF (843/871°c).

Soak and cool very slowly in the furnace. Brinell approximately 223.

Intermediate or process annealing treatment---heat uniformly to 1350/1400ºF (732/760°c).

May be cooled in the furnace or air cooled. Brinell hardness about 230.

Hardening

Preheat to 1400/1500ºF (760/816°c), then heat to 1850/1950ºF (1010/1066°c); soak; quench in warm oil or cool in air.

Do not overheat. When overheated, full hardness cannot be obtained.

Tempering

Hardness of approximately Rockwell C 56/57 will be obtained on this steel.

To remove peak stresses and yet retain maximum hardness temper at least one hour at 300/350ºF (148/176°c).

Contact:LIU

Email: sales@ahoneststeel.com

Cell:0086 18915272882