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TiAlLaN coatings were deposited on the cemented carbide substrates by mid-frequency magnetron sputtering system. The effects of Ar/N2 flow ratio on the composition, structure, adhesion and hardness followed with elastic modulus and H/E ratio were investigated systematically. Results indicate that all the Ti/Al ratios of the coatings were higher than that of the Ti/Al ratio in the target; however, the Ti/Al ratio increased with the Ar/N2 flow ratio changed. XRD patterns show that the intensity of (111) peak was elevated with the Ar/N2 flow ratio increased. Meanwhile, the peak shifted to lower angles, which implied increases of the lattice parameter. The TiAlLaN coating under the Ar/N2 flow ratio of 3:1 showed the best adhesion, the highest hardness and the lowest H/E ratio which indicated perfect wear resistance.

Fe2O3/Al2O3 composite at the mass ratio of 3:2 was prepared by sol-gel combustion synthesis using urea as fuel. The optimized preparation parameters were determined by the robust orthogonal experimental design (OED) method. Standard L9(34) orthogonal array was adopted, and the four factors were determined as the molar ratio of oxidizer nitrates to fuel urea Ф, relative amount of the deionized water added Rw, ignition temperature and sintering temperature. Range analysis of the relative importance of those four factors on the mean weight loss rate for the reduction of synthesized Fe2O3/Al2O3 with 50 vol% H2 indicated that the most influential factor was Ф, sintering temperature, Rw and ignition temperature in the descending order. And the optimized preparation parameters for Fe2O3/Al2O3 composite were Ф=1, Rw=7.5, ignition and sintering temperatures stabilized as 600oC and 950oC,respectively. Finally, the reaction characteristics of Fe2O3/Al2O3 prepared by SGCS and the other two reference methods (including sol-gel method and mechanical mixing method) were compared and the results verified that the optimized SGCS was the best option to synthesize Fe2O3/Al2O3 composite with good reaction performance.

Sol-gel combustion synthesis method was adopted to prepare nano-sized CoFe2O4 using urea as fuel. The as-synthesized CoFe2O4 powders were characterized through such experimental means as Fourier transform infrared spectroscopy (FTIR), TG (thermogravimetric)–DSC (differential scanning calorimetry), X-ray diffraction (XRD), field-scanning electron microscopy (FSEM). FTIR analysis and XRD analysis revealed that the dried CoFe2O4 gel was formed by the coordination of metal with O, and consisted of various phases through the hydrolysis of urea and metal nitrates along with the coordination of the various groups produced. And then, TG-DSC analysis of the dried CoFe2O4 gel under air atmosphere indicated that there are two remarkable exothermic reactions occurring, related to the redox reactions between urea and nitrates used, and as-synthesized CoFe2O4 was porous due to the emission of large amount of gases during preparation. Finally, three cycles of temperature-programmed reduction (TPR) coupled with temperature-programmed oxidization (TPO) tests were conducted on the AutoChem 2920 system to show the good reaction and sintering-resistance performance for the synthesized CoFe2O4.