- 截稿日期延期至 2020年4月20日
Biography: Dr. Henry Hu is a tenured full Professor at Department of Mechanical, Automotive & Materials Engineering, University of Windsor. He was a senior research engineer at Ryobi Die Casting (USA), and a Chief Metallurgist at Meridian Technologies, and a Research Scientist at Institute of Magnesium Technology. He received degrees from University of Toronto (Ph.D., 1996), University of Windsor (M.A.Sc., 1991), and Shanghai University of Technology (B.A.Sc., 1985). He was a NSERC Industrial Research Fellow (1995-1997). His publications (over 150 papers) are in the area of magnesium alloys, composites, metal casting, computer modelling, and physical metallurgy. He was a Key Reader of the Board of Review of Metallurgical and Materials Transactions, a Committee Member of the Grant Evaluation Group for Natural Sciences and Engineering Research Council of Canada, National Science Foundation (USA) and Canadian Metallurgical Quarterly. He has served as a member or chairman of various committees for CIM-METSOC, AFS, and USCAR. The applicant’s current research is on materials processing and evaluation of light alloys and composites. His recent fundamental research is focussed on transport phenomena and mechanisms of solidification, phase transformation and dissolution kinetics. His applied research has included development of magnesium automotive applications, cost-effective casting processes for novel composites, and control systems for casting processes. His work on light alloys and composites has attracted the attention of several automotive companies.
Topic: Advanced Processing of Aluminum Alloy for Lightweight Automotive Applications: Heat Transfer Modeling
Abstract: Aluminum alloy A380 is widely used for various automotive components made by high pressure die casting (HPDC) processes. The HPDC A380 has moderate mechanical properties due to its relatively high porosity content. It has demonstrated that squeeze casting (SC) is capable of eliminating porosity and improving the mechanical properties of A380. But, studies on heat transfer phenomena occurring during squeeze casting of A380 are limited. In this study, a step die was made by P20 steel for squeeze casting aluminium alloy A380 with five different section thicknesses of 2, 4, 8, 12, and 20 mm under an applied pressure of 90 MPa. K-type thermocouples were employed to measure temperatures of the squeeze casting surfaces as well as three different depths, i.e., 2, 4, and 6 mm from the die inner wall at each step. With the temperature measurements, interfacial heat transfer coefficients (IHTC) at the casting and die inner surface and heat fluxes were determined by solving one-dimensional heat conduction formulae using the inverse method. The results of the calculated IHTCs showed that, upon the commencement of squeeze casting, the IHTC values for all the 5 steps rose rapidly. Before decreasing, the IHTC at each step reached its own individual pinnacles. As the section step thickness changed from 2 mm (step 1) to 20 mm (step 5), the IHTC peak values increased significantly. It took longer time for a thicker step to reach its peak IHTC value, and also to drop its IHTC to a low and steady level.