Isothermal precision forming of magnesium alloy upper housing

Upper housing,a key part of helicopter,is difficult form due to its big size and complex geometry and stringent requirements for its properties.Isothermal forging was therefore used and the forming temperatures range from 350～360 ℃.The Combined die structure and local loading method were adopted.The upper housing was forged successfully by isothermal precision forging.The mechanical properties、micro、macro structures and accuracy of the component can satisfy the requirements of the user.