Effects of Nano-Al<sub>2</sub>O<sub>3</sub> on the Mechanical Property and Microstructure of Nano-Micro Composite Self-Lubricating Ceramic Tool Material

A new nanomicro composite self-lubricating ceramic tool material was prepared with vacuum hot pressing technique. The effect of nanoAl 2 O 3 powders on the microstructure and mechanical properties of nanomicro composite self-lubricating ceramic tool material was investigated. With the increase of nanoAl 2 O 3 content, the hardness and fracture toughness first up then down. When the nanoAl 2 O 3 content is 4 vol.%, the flexural strength, hardness and fracture toughness reaches 562 MPa, 8.46 MPa·m 1/2 and 18.95 GPa, respectively. The microstructure and mechanical property of nanomicro composite self-lubricating ceramic tool material can be improved by the grain refinement strengthening of nanoAl 2 O 3 .