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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.

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.

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.

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.

The purpose of this paper is to investigate the effects of two different weight percentages of lanthanum on tin–zinc–antimony solder alloys. Two manufacturing techniques were used: the furnace melting method (FMM) and ball milling method (BMM). The alloys were characterized and mechanically tested.

Tin–zinc–antimony alloys with 0.5 and 1% lanthanum were prepared by FMM and BMM for 25, 30 and 35 h. The tensile, shear, hardness, wear and corrosion properties were characterized using optical microscopy, scanning electron microscopy and X-ray diffraction.

Ball-milled samples were harder and more resistant to wear than furnace-melted samples. Corrosion tests showed that ball-milled samples of both the 0.5 and 1% lanthanum tin-based solders showed higher corrosion than furnace-melted samples. The ball-milled samples exhibited a uniform particle distribution. The ductility of the milled samples was significantly higher than that of the furnace-melted ones. There was strong evidence of the presence of nanoparticles. X-ray diffraction revealed some amorphous phases, which have not been previously reported.

The quality of solder alloys prepared by FMM and BMM was compared. This comparison was not made in previous studies. In addition to the hardness, the wear and corrosion resistances were measured, which have not been previously reported. There seems to be evidence of the presence of nanoparticles in the solder, as suggested by the increase in the elongation. Tensile, elongation and shear tests were performed, and a theory was provided for the results obtained.