Structure and Deformation Characteristics of Rheocast Metals.
Abstract
This is the first annual report describing research at the University of Illinois at Urbana-Champaign, aimed at establishing the feasibility of producing parts to net or near-net shapes starting with Rheocast preforms by forging-type, THIXOFORGING, operations. Ingots of Sn-15% Pb alloy and aluminum alloys 6061 and A356 were heated to temperatures above liquidus and in the liquid-solid range. The partially solidified charge, Rheocast, materials were previously made in a continuous slurry producer. Sound flanged shaped cup parts with good mechanical properties and unidirectionally solidified cylinders were produced in a 50-ton hydraulic press. Die thermal behavior was experimentally determined from thermocouples located at different distances from the metal-die interface. Measured maximum die temperatures were lower when the initial charge material was partially solid or when applied pressure was reduced. A one-dimensional computer heat flow program was developed to simulate heat flow in the cylinder parts and the steel dies. Correlation of computer predictions and measured temperatures were used to calculate values of the heat transfer coefficients at the metal-die interface prior to and after pressurization. The heat transfer coefficients increase by one order of magnitude or more upon application of 9.1 x ten to the 7th power Pa pressure.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1977
- Accession Number
- ADA049975
Entities
People
- D. G. Backman
- G. J. Abbaschian
- R. Mehrabian
- S. D. E. Ramati
Organizations
- University of Illinois Urbana–Champaign