Effect of Heat Treatment on the Mechanical Properties of Copper-Beryllium Alloy (C17200)

Owing to high elastic modulus and good strength, copper beryllium alloys are widely used in many engineering applications. The addition of beryllium to copper makes the alloy respond to aging treatment and thus develops very high strength. Conventional heat treatment cycles are available for copper-beryllium to obtain peak ageing hardness condition. Present study has focused on developing a heat treatment cycle to obtain synergetic combination of moderate strength and good toughness for the C17200 copper-beryllium alloy. Ageing curves have been generated for varying temperature and time. Detailed mechanical properties (hardness, impact, tensile) evaluation at room temperature and sub-zero temperatures have been carried out for the selected samples. Modified heat treatment cycle resulted in higher toughness with adequate strength. Optical microscope (OM) and transmission electron microscope (TEM) analysis were carried out to understand the precipitation behavior. Also, measurements of coefficient of thermal expansion (CTE) and thermal conductivity were carried out on the aged samples.