Evaluation of plastic strain caused by ECAP and HPT processes through finite element analysis method

Applying SPD on metalic materials in order to form a nanochrystal structure has been the subject of many recent researches. Researches show that nanochrystal structureimproves mechanical properties such as yielding strength and wear resistance against abrasion. Among SPD methods, HPT and ECAPmethods have been more popular. Irrespective of the different geometry of the parts produced through each of these processes, studying the amount of plasticdeformation as well as the method of applying it could be useful in each of these processes, when it comes to comparing and choosing themore effective process. In this article, the results of finite element analysis of the HPT and ECAP processes onpure commercial is provided and the rate ofsuccess of each one in applying the SPD to the part is studied. As a result of the high pressure in the HPTprocess and the constant circular deformation that is applied, the amount of plastic deformation applied in the HPT process is more than that of the ECAP process.Therefore it could be said that more grain efinement could be obtained in metals through the HPT process. According to the results of simulation and inaccordance with the existing experimental reports, as the process continues and the number of rotations is increased, the plastic deformation at/on any point of the disc is constantly increased. Since increasing the number of rotations in the HPT process is much easier than repeating thepasses in the ECAP process, it could be said that applying plastic deformation in the HPT process is much easier and faster than in the ECAP process.

کلیدواژه ها:

HTP ، ECAP ، nanochrystal ، finite element ، plastic deformation ، grain refinement ، mechanical properties