STUDY OF TEXTURE EVOLUTION DURING CHANNEL-DIE COMPRESSION OF MG-AL ALLOYS BY IN-SITU NEUTRON DIFFRACTION

摘要

The significant weight saving afforded by magnesium alloys has been demonstrated in many research projects in the automotive, aviation, machine tool, and consumer electronics industries. Major problems in the large-scale application of magnesium alloys are poor formability, low corrosion resistance, and creep. The properties of magnesium can be improved dramatically by the addition of a broad variety of alloying elements. Casting, downstream operation, and heat treatment are all effective tools in achieving optimized material performance at a competitive cost. Although these important mechanical properties can be strongly affected by crystallographic texture, there is little in the way of in-depth studies have been reported in the literature. Particularly, improvements in properties reported are rarely supported by an analysis of the corresponding modification of the texture. The present study contributes to the general understanding of texture evolution during rolling of binary Mg-Al alloys. A jig for high-temperature in-situ channel die compression has been designed and fabricated at the Canadian Neutron Beam Centre (CNBC) with a purpose to simulate industrial rolling operation. The high penetrating power of neutrons allows data to be collected from the alloy during deformation. It is shown that the observed texture evolution can be attributed to a combination of {1012} twinning and basal slip.