Low Temperature Warm Forming of Magnesium ZEK 100 Sheets for Automotive Applications

Abstract

Cosma R&D investigated a low temperature warm forming process by which a magnesium ZEK 100 door inner part with a single-stage draw depth of 144 mm was successfully formed. The warm forming process is comprised of three steps: 1) heating pre-lubricated blanks in an oven at temperatures ranging from 215°C to 260 °C, 2) robotic transfer of the heated blank to a mechanical stamping press, 3) forming of the panel in room temperature stamping die at speed of about 160 mm/s. The effect of process parameters on the formability of the part, as well as, the post-forming properties including the mechanical properties, microstructure evolution and deformation thinning are also presented. The result indicates that Magnesium ZEK 100 exhibits superior low temperature warm formability over Magnesium AZ31B, and the developed warm forming process is promising and potential for volume production of magnesium automotive parts.

Cyclic deformation and anelastic behavior of ZEK100 magnesium alloy: Effect of strain ratio

“…A comparable s UTS value for the ZK60 alloy ( $ 302 MPa with 1.3 wt% Gd) was reported by He et al [52]. A superior ductility for ZEK100 alloy was noted, and was related to its decreased stacking fault energy facilitating the non-basal dislocation slip [49] and improved formability [30]. That is, a higher ductility of 13.3% (Table 1) was obtained for the ZEK100 alloy with respect to 8.3% for GW103K [51] and 13% for AM30 [17].…”

“…Niu et al [30] reported that ZEK100 alloy possessed superior warm formability over AZ31B alloy, indicating the potential for the volume production of magnesium automotive parts. This alloy also exhibited superior true fracture strains (i.e., up to 60% higher than the commercial AZ31B alloy for all strain paths at all temperatures and strain rates applied [31]).…”

Film Breakdown and Nano-Porous Mg(OH)2Formation from Corrosion of Magnesium Alloys in Salt Solutions

“…The E717 alloy has recently been shown to be amenable to formation of door panels by warm forming techniques, making it of particular interest to automotive applications. 44 Analyzed compositions are shown in Table I. The AZ31B and E717 sheet material was used for SANS study as nominal ∼25 mm × 25 mm × 1.5 mm rectangular test samples prepared to a 1200 grit surface finish wet ground with SiC paper, cleaned with acetone and deionized water, and dried with an air stream.…”

Strain-controlled low cycle fatigue properties of a rare-earth containing ZEK100 magnesium alloy

“…The formability of this alloy in a two-stage forming process with intermediate annealing was also studied [33]. ZEK100 alloy exhibited superior warm formability over AZ31B alloy, indicating the potential for the volume production of magnesium automotive parts [34]. The tensile properties and constitutive behavior of ZEK100 alloy was also studied at varying strain rates and sample orientations at room temperature [35][36][37].…”