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Instead of conventional quenching and tempering, fast austenitization from an initial microstructure of lamellar pearlite followed by quenching and tempering was carried out, leading to the formation of inhomogeneous microstructure. It comprised different morphologies of lath martensite and retained austenite (RA). The effect of tempering temperature on microstructure evolution and tensile properties was systematically investigated. With increasing tempering temperature from 150 to 250 °C, transition carbides gradually coarsened and their amount increased, the dislocation density in martensitic laths gradually decreased, and RA fraction decreased from 10.9% to 2.2%. The precipitation and dislocation strengthening can ensure a high strength, while RA can ensure a good ductility, leading to a simultaneous increase in the strength and ductility when decreasing tempering temperature. Specifically, the best combination of tensile properties (ultimate tensile strength of 2133 ± 41 MPa and total elongation of 11.1% ± 1.3%) was achieved after tempering at 150 °C.

Instead of conventional laminated composite fabricated in industry, the present study successfully, for the first time, produced nacre-like TiNi/Ti2Ni brick-and-mortar composite using industrial hot pressing and hot rolling. In comparison with laminated composite, this brick-and-mortar composite not only exhibited larger compressive strength and flexural strength but also showed higher ductility and initial fracture toughness. These excellent mechanical properties were originated from the brittle Ti2Ni bricks homogenously distributed among the ductile TiNi mortars. Attentionally, this brick-and-mortar microstructure inhibited the delamination between brittle and ductile constituents by stopping the easy crack propagation along the brittle constituent.

Nano-structured and micron Al2O3-13%TiO2 coatings were deposited by air plasma spraying.Wear properties of the coatings under different temperature trough SRV friction and wear testing machine were studied, the results shows that the friction coefficient of nano and micron Al2O3-13%TiO2 coatings both have rising trend.with the temperature increases.The wear volume of micron coating is 1.8-2 times that of the nano coating..The nanometer Al2O3-13%TiO2 coating slide with ZrO2 is still compact and has no large crack after abrasion.

Cutting steel is required to have high wear resistance with certain hardness and deformation resistance. The commonly used machinery material for meat processing in china is 4Cr13, which is far inferior to the imported German steel X80CrVMo13-2. After studying the influence of different heat treatment process on its wear resistance, we have come to the following conclusion: X80CrVMo13-2 steel, after quenched at 1050°C and tempered at 500°C, has an excellent wear resistance and 4Cr13 steel, after normalized at 1010°C and tempered at 500°C has a fairly good wear resistance.

Nano-structured Al2O3-13%TiO2 coating was deposited by air plasma spraying. Wear properties of the coatings under different load trough SRV friction and wear testing machine were studied, the results showed that wear mass loss of Al2O3-13%TiO2 coating by plasma spraying slide with ZrO2 and Si3N4 increase with load increasing, but the difference is that wear loss of coaing slide with Si3N4 ¬is lower than the coating slide with ZrO2 when load is less than 40N. Opposite phenomenon will occur when load is higher than 40N.The wear surface morphology was analyzed trough scanning electron microscopic, the results showed that coating slided with Si3N4 ball when matching at low loads, with a shallow furrow shape grinding. There were wide and deep furrows while at higher loads. Coating slide with ZrO2 ball has no obvious cracks, no layer spalling.Wear was occurred by micro cutting.

Nanometer Al2O3-13%wtTiO2 wear-resistant coating was prepared by The plasma spraying process , and the coating was tested through a SRV friction and wear testing machine, the worn surface and wear debris were observed by scanning electron microscopy, and the wear mechanism was analyzed. The friction coefficient of Nanometer Al2O3-13%wtTiO2 decreases with the increase of the load. The main wear mechanism is adhesive wear, accompanied by a small amount of abrasive wear.