Molecular Dynamics Study on Mechanical Properties of Nickel-based Single Crystal Superalloys Containing Voids

Nickel-based single crystal superalloys have been widely used in aerospace due to their superior properties,but there are inevitable void defects in the manufacturing process,which affect the mechanical properties of the alloy. The effects of temperature,strain rate and void shape on the tensile mechanical properties and dislocation evolution of nickel-based single crystal superalloy have been studied by molecular dynamics simulation. Results show that temperature and strain rate affect the mechanical properties of materials. With the increase of temperature, Young’s modulus,yield strength and material strength are all decreased;With the increase of strain rate,the young’s modulus of the material remains unchanged and the yield strength increases. In addition,the presence of voids reduces the strength and Young’s modulus of the material. Young’s modulus of models with different shapes of voids is the same,while strength of those is different. Due to the acute angle of the diamond-shaped void,the dislocations are more likely to aggregate,the yield strength is smaller,and it is more likely to be broken during the stretching process. © 2023 Cailiao Daobaoshe/ Materials Review. All rights reserved.