A2 Flat Ground, is an air hardening chromium alloy die steel that replaces O1 Flat Ground when safer hardening, less distortion and increased wear resistance are required. Characteristics of A2 Flat Ground include - good machinability, high compressive strength, very good non-deforming properties, deep hardening, and high dimensional stability after hardening and tempering. A2 Flat Ground is ground to a surface finish of up to 35Ra on six sides and is free from defects and decarburization. Sold in annealed state to be heat-treated.
Hardness*
27 HRC
Corrosion Resistance
Low
Machinability
Medium
Depth of Hardening
Deep
Weldability
Difficult
Grindability
Wear Resistance
High
Distortion in Heat Treating
Lowest
Overall Toughness
Decarburization Resistance
Strength
Resistance to Heat Softening
* Can be hardened up to Rockwell C65Data provided for references only and is not warranted.