Manufacture of magnesium alloy screws

Abstract

This study reports the fabrication of LZ91 magnesium alloy screws using warm heading and thread-rolling processes. The proposed method consists of a two-stage warm heading process. This study presents an analysis of the material flow pattern of the billet inside the die by using finite element analyses. This study also presents the effects of upper die velocity, temperatures, and friction factors on the heading loads and product quality. This paper also investigates the effects of the friction factor on the effective stress, effective strain, and tooth height in a thread-rolling process. Finally, warm heading and thread-rolling experiments were conducted using a self-designed die set and a MoS2 lubricant. This study presents a comparison of the experimental values with the simulation results to verify the validity of the finite element models and the proposed warm heading procedures.