Heat Treatment

Heat Treatment for Sand and Gravity Die Castings

Heat treatment is used to improve the mechanical and physical properties of aluminium castings, primarily to increase the tensile strength and reduce the ductility (stretch) of the metal.

Heat treatment is carried out in a highly controlled manner in specialised furnaces to ensure that the casting retains its original shape without cracking. The temperature is kept within very strict parameters to ensure that the casting complies with the required specification.

Our heat treatment processes

At Haworth Castings, we use various heat treatment conditions to produce the different degrees of hardness required for our castings, namely:

• Water quenching
• Stress-relieving
• Polymer quenching
• Crack detection

Once treated, the hardness of the casting is measured on the Brinell scale (in HB units) – which is a nationally recognised standard. The castings can then be put through crack detection analysis to check for any defects.

To read a full overview of the heat treatment process please click here.