There has been a growing demand for safety parts with tailored properties in automobile industry.However,the understanding of tribological behavior of press hardening steels(PHS)on the tailored conditions is highly in...There has been a growing demand for safety parts with tailored properties in automobile industry.However,the understanding of tribological behavior of press hardening steels(PHS)on the tailored conditions is highly inadequate.The present work aims at creating new knowledge about the tribological characteristics of PHS on the tailored conditions and bridging this existing gap.The paper proposes an improved hot drawing tribo-simulator to simulate the realistic experimental conditions industry.Investigations were carried out on the condition of different initial heating temperatures,tool temperatures,austenitizing temperatures,cooling rates and microstructures.The presented results show that the whole frictional process is divided into three stages for both coated and uncoated steels.The frictional factor changes a lot and the peak value of frictional factor occurs for serious adhesive wear.The frictional factor rises as the tool temperature and austenitizing temperature rise.The surface morphology of tools indicates that the coating adhering to tool gets thicker as the tool temperature increases.With the increase of cooling rate,the frictional factor declines firstly and then rises to some extent.Flat dies with different temperatures are used to form specimens with different microstructures,which also affects the frictional factor and wear.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.51275185 and 51405171)the National Basic Research Program of China("973"Project)(Grant No.2010CB630802-3)+1 种基金the Fundamental Research Funds for the Central Universities(HUST,No0118110621)the Graduate Innovation and Entrepreneurship Fund of Huazhong University of Science and Technology(HUST,No.0109070112)
文摘There has been a growing demand for safety parts with tailored properties in automobile industry.However,the understanding of tribological behavior of press hardening steels(PHS)on the tailored conditions is highly inadequate.The present work aims at creating new knowledge about the tribological characteristics of PHS on the tailored conditions and bridging this existing gap.The paper proposes an improved hot drawing tribo-simulator to simulate the realistic experimental conditions industry.Investigations were carried out on the condition of different initial heating temperatures,tool temperatures,austenitizing temperatures,cooling rates and microstructures.The presented results show that the whole frictional process is divided into three stages for both coated and uncoated steels.The frictional factor changes a lot and the peak value of frictional factor occurs for serious adhesive wear.The frictional factor rises as the tool temperature and austenitizing temperature rise.The surface morphology of tools indicates that the coating adhering to tool gets thicker as the tool temperature increases.With the increase of cooling rate,the frictional factor declines firstly and then rises to some extent.Flat dies with different temperatures are used to form specimens with different microstructures,which also affects the frictional factor and wear.
