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The microstructure and mechanical properties was studied for API (American Petroleum Institute) X90 pipeline steel bend, which was formed by local induction heat. It was found that X90 pipeline steel parent microstructure consisted of quasi-polygonal ferrite, granular bainite and a small amount of M/A constituents, which provided a good mechanical property. The yield strength, tensile strength, and yield ratio was 786, 876 MPa, 0.90, respectively. After local induction bending, strain-induced phase transition behavior occurred within the deformation zone. The neutral axis position was almost free from force, for quenching-tempering microstructure with small grains.

A novel synthetic copolymer (PAA) for bone repair was prepared by melt condensation polymerization with 6-aminohexanoic acid (He) and 4R-hydroxy-L-proline (Hyp). The structure and thermal property were characterized by infrared spectrometer (IR), nuclear magnetic resonance (H1NMR) and differential scanning calorimeter (DSC). The results indicated that the PAA had amide linkages in their polymer chains. The Tg of PAA was 57.56°C and significantly higher than that of nylon6, 50.46°C. Meanwhile, the intrinsic viscosity and mechanical properties were investigated at different He/Hyp ratios. It revealed that appropriate introduction of Hyp group could control the degree of polycondensation and adjusted mechanical properties of PAA obviously close to natural bone. The prepared polymers had about 2.12~18.21 % weight loss after 8-week soaking in PBS, showed degradable properties which was essentials to new bone growth. The copolymer of He and Hyp with ratios of 90/10 had 6.57 % weight loss and maintained the yield compressive strengths with about 67.51 MPa after 8 weeks, which exhibited a compatible mechanical properties and degradation speed for bone repair.

Single-phase aluminum oxynitride powders were obtained by varying the holding temperature (T) and the weight percentage of α-Al2O3 in Al2O3 (X) with nano-sized Al2O3 and AlN powders as raw materials. Influences of T and X on the phase composition of obtained powders were studied. The results showed that the content of aluminum oxynitride increased with increasing T or X. When X was 50% and T was 1750°C, obtained powders had better properties than those of others.