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The three kinds of WC-12Co coatings were sprayed by High Velocity Oxygen/Air Fuel Spray (HVO/AF) in three different spray conditions, HVOF、HVO-AF and HVAF. The high velocity flame flow was produced by HVO/AF with the burning of kerosene and propellant which was mixed by oxygen and air at different ratio, it can be controlled from 1400℃ to 2800℃.The microstructure was investigated by SEM, the phase composition was tested by XRD, and the microhardness and elastic modulus of coatings were investigated. The results indicate that the coatings with better adhesive strength and little porosity than conventional ones are dense and have a large value of elasticity and a high microhardness which is 0.4 times harder than the conventional coatings. The coatings are mainly composed of WC and Co, and there are also traces of W2C and Co6W6C. As temperature decreased, the decomposition of WC is being reduced.

C/C composite material is widely used as the insulation material since its advantage is obvious compared with other materials. It is necessary to evaluate its ablation, especially when it used in the warhead. An ablation/erosion test system based on plasma is researched. All the parameters related to the plasma can be monitored by it to calculate the enthalpy. Two ablation tests of the C/C composite material are carried by this system. The ablation of the carbon fiber and the erosion of the particle are mainly analyzed by the measure of the ablation rate and the SEM photos.

In this paper, the nano-β-SiC/Al2O3 composite absorbing coatings produced by plasma spraying technology were reported. Where, β-SiC phase dissipates in the boundary of Al2O3 grains. Then, the relationship between microstructure and dielectric properties was built. Some results are shown as follows: with increasing of flatten ratio of particle and pores, the microwave reflectivity coefficient of composite absorbing coatings decreases and ranges to low frequency. And, there exists a threshold value, about 30wt% of nano β-SiC, the microwave reflectivity coefficient of composite absorbing coatings can reach to -8 dB. The infrared properties of β-SiC/ Al2O3composite absorbing coatings with experiment is about 0.6~0.8, respectively.

Environmental protection and worker safety measures against the extensively used hard chrome plating (EHC) is becoming more stringent, which leads to the development and application of alternative technology. As one of the most promising replacement technology of EHC, WC/Co coatings deposited by High Velocity Oxygen Fuel (HVOF) have well performances in corrosion and wear resistance. The paper analyzed technical characteristics, property and cost of EHC and HVOF deposited WC-Co coatings, while results show that performance of HVOF sprayed WC-Co coatings is superior or equal to EHC with much higher expense, so current replacement of EHC by HVOF centers airplane and military arm field which have relatively higher profit.

The jet temperature of the plasma generator for waste disposal reaches as high as 10000K so that it is difficult to measure directly. By constructing a digital plasma measurement system, the operating parameters of plasma generator can be precisely controlled and measured. According to energy balance principle, the mathematical model was determined to calculate the average enthalpy at the plasma generator exit plane, and the average temperature and its distributions were obtained. Influence of different gas compositions on plasma jet characteristics was studied. The results show that, at the plasma generator exit plane, the maximal temperature and average temperature of argon plasma jet is about 18794K and 10193 K respectively, while that of argon-hydrogen plasma jet is about 22358 K and 12100 K.

The self-lubricating coating which is dense in microstructure with low porosity and degradation is sprayed by HVOF and the spray powder is Nickel coated MoS2 with 22%wt of MoS2. The mean bonding strength and hardness of Ni-MoS2 coating is respectively about 13.68 MPa and HRB94.5. Tribological performance is evaluated by the test of dry friction coefficient, which fluctuates from 0.25 to 0.32, while the wear granule is symmetry with a uniform distribution in size, moreover, the experiment results indicate the main wear failure mode of coating is abrasive wear.