The isothermal precision forging process and microstructure evolution of Mg-RE component with highrib
and thin-web are studied in the article. The deform software was used to simulate the isothermal precision forging
process and some problems arises during the forging process were proposed. Some methods are also proposed according
to the results of simulation and the forgings with high-rib and thin-web were formed successfully. The results show that
the intersected lateral ribs are difficult to fill during isothermal precision forging process. The dimension of billet is optimized
according to the simulation analysis by deform software, which reduces the load of forging process and the Mg
-RE component with high quality is formed successfully in the combined female dies. The optimal ageing parameter,
200℃,63 h, is obtained,corresponding to peak ultimate tensile strength,tensile yield strength and elongation of the
Mg-RE component of 371 MPa,243 MPa and 4. 07%,respectively. The strengthening β′ phase and long period stacking
ordered phase mainly contribute to the high strength of the component. The fracture modes are changed during
forging process and ageing process, i. e. ductile fracture in the forged component and cleavage fracture in the aged
component