Papers by Author: Ning Liu

Abstract: In this paper, a novel method to measure the footprint pattern of a vehicle tire and its pressure distribution will be put forward. The measurement principle will be presented. The automatic digital image processing methods of the footprint pattern and pressure distribution images, which are used to characterize the footprint pattern, are described. Especially, a novel envelope curve calculation algorithm for finding a pattern boundary is introduced. The experimental results have shown that the methods mentioned in the paper are of robustness and high accuracy.

Abstract: The two cutting tools obtained from ultra-fine grade Ti (C,N)-based cermets were tested in the dry cutting of a medium carbon steel (AISI1045). Microstructure and mechanical properties were studied. Wear mechanisms (mainly diffusion and oxidation) were investigated in detail and compared each other in order to better understand key aspects due to thermal wear mechanisms. Comparing tool A with B, under the adopted cutting conditions, the tool A has a better resistance to oxidation deformation in machining medium carbon steel due to the higher hardness, although tool B has higher bending strength and fracture toughness.