Investigating anvil alignment and anvil roughness on flow pattern development in high-pressure torsion

Authors: Huang, Y., Kawasaki, M. and Langdon, T.G.

Journal: MRS Advances

Volume: 1818

Pages: 1-12

eISSN: 2059-8521

ISBN: 9781510872356

DOI: 10.1557/opl.2016.79


High-pressure torsion (HPT) is a processing technique in which samples are subjected to a high pressure and torsional straining. Anvil alignment and anvil roughness are two important factors related to the successful application of the HPT processing technique. Using a two-phase duplex stainless steel as a model material, experiments were conducted by placing the anvils in different amounts of initial misalignment. Experiments show that the flow patterns (the development of double-swirl patterns) in HPT are dependent upon the alignment of the anvils within the HPT facility. Through carefully designed experiments, it is shown that the presence of a double-swirl is a feature of HPT processing when the initial positions of the anvils have a small lateral misalignment. The effect of the double-swirl patterns on the hardness evolution was also evaluated quantitatively. By comparing the flow patterns developed on the disc upper surface using both rough and smooth anvils with a fixed anvil misalignment, it was demonstrated that there are some differences in the flow patterns which are dependent upon the anvil surface roughness.

Source: Scopus