Ausbay quenching

Quenching technique (limited to certain high strength alloy steels) that reduces the residual internal stresses and distortion resulting from non-uniform transformation and thermal shock typical of conventional oil quenching.

Benefits

Reduction in residual stress and distortion as compared to conventional oil quenching of selected high strength steels.

May permit heat treatment of near net shape parts and minimise required machining/grinding of components after heat treatment.

Application & materials

Applicable to certain high strength alloy steels such as 300M (4340M) and D6AC. Ausbay quenching is recognised by several aerospace heat treating specifications. Current applications include structural components in aircraft applications (300M/4340M) and military gun barrels (D6AC).

Limited to alloy steels that exhibit an adequate “Ausbay” on their TTT (Time-Temperature-Transformation) curve. 300M (4340M) and D6AC are the alloys most commonly Ausbay quenched.

Process details

Minimising residual stress and distortion while achieving mechanical properties (hardness, tensile strength, fracture toughness, etc.) equivalent to those obtained with conventional quenching, greatly reduces the risk of cracking during heat treatment.