2000 Volume 18 Issue 4 Pages 657-666
The wear phenomenon occurs in most parts of the industrial machines by dynamic contacts between the parts and collisions with powder like a ash. The wear causes deterioration of the performance of the machines. The wear resistance materials have been developed by a thermal spraying, an overlaying, and various methods of the casting etc. In this study, composite materials consisting of alumina ceramics beads or hard metal beads and copper as a matrix were developed using HIP method. The influence of the HIP processing condition on bending strength and abrasive wear characteristics of the composites were examined. Main results obtained are as follows. (1) The separation of the alumina beads from the alumina-reinforced materials during grinding process was decreased largely when the composites were made of Ti-coated alumina beads treated by an attritor. (2) Though three point bending strength of the alumina-reinforced materials varied considerably, the maximum bending strength was greater than 200 MPa. (3) Cracks were initiated in the alumina beads of the alumina-reinforced materials during HIP processing. However, the cracks were decreased when the pressure of the HIP was lowered to 5 MPa. (4) The bending strength of the hard metal-reinforced materials varied from 360 to 580 MPa. It was higher value than that of the alumina-reinforced materials. (5) The abrasive volume loss of the composite with the Ti-coated alumina beads was about 1.8 times lower than that of the composite with the alumina beads without the attritor treating. The abrasive volume loss of the hard metal-reinforced materials was about twice lower than that of the alumina-reinforced materials. (6) The abrasive wear characteristics of the alumina-reinforced materials and the hard metal-reinforced materials were strongly superior to those of the copper.
