The microstructure and high-temperature tribology behavior of high boron HSS under different heat treatments

Abstract

Purpose The purpose of this paper is to study the microstructure and the high-temperature tribology behavior of a high-speed steel (HSS) roller material with boron as the main alloy element under different heat treatments, aiming to provide some theoretical references for its engineering application. Design/methodology/approach The samples of high boron HSS were quenched at 900°C, 1,000°C, 1,050°C and 1,150°C. The microstructure, composition and phase composition of this new HSS were analyzed by OM, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS) and X-ray diffractometer. The surface hardness and the tribology behavior under high temperature were measured by Rockwell hardness tester and the high-temperature friction and wear tester. The wear morphology was observed by SEM. Findings The high-temperature friction coefficient and the relative wear rate of the high boron HSS decrease first, then increase with the rise of the quenching temperature. When the quenching temperature is 1,050°C, both the friction coefficient (0.425) and the relative wear rate (79 per cent) are the smallest. Under the high-temperature friction environment, the high boron HSS mainly includes oxidation wear, adhesive wear and abrasive wear. The effect of abrasive wear is weakened gradually with the rise of the quenching temperature, and the high-temperature wear resistance is improved significantly. Compared with the traditional roll materials, the service life of the new high boron HSS is greatly improved. It is an ideal substitute product for the high chromium cast iron roll. Originality/value The boron element replaces other precious metals in high boron HSS, which has the advantage of low production cost, and it has a wide application in the field of roll materials. In this paper, the microstructure, the transformation of hard phases and the high-temperature tribology behavior of this new high boron HSS under different heat treatments were studied, aiming to provide some theoretical references for its engineering application.

Effects of Boride Orientation and Si Content on High-Temperature Oxidation Resistance of Directionally Solidified Fe–B Alloys

“…Accordingly, the unique microstructures and properties of Fe–B alloys can be easily regulated by wide-range adjustment of the boron and carbon contents to control the hard-phase and anti-corrosive Fe 2 B and the continuously distributed metal matrix, which achieves independent control of the wear-resistant phase and matrix structure. Therefore, this alloy has better hardenability, fracture toughness and wear resistance compared to other iron-based alloys and steels [ 11 , 12 , 13 , 14 , 15 , 16 , 17 ]. As the primary alloying element, the high-temperature corrosion behaviors of borides have been investigated widely.…”

Effect of quenching media on microstructural evolution, mechanical and wear properties of AISI4135 steel

“…13 It was reported that the microstructures with full martensite and up to 35% retained austenite were observed with different amount of carbide formation. Zhentao et al 14 studied the effect of various heat treatments on microstructures and tribological behavior of boron based HSS. The samples of steels were heated and quenched at various temperatures.…”