Ablation under oxyacetylene torch with heat flux of 4186.8 (10% kW/m2 for 20 s was performed to evaluate the ablation resistance of C/C–SiC composites fabricated by chemical vapor infiltration (CVI) combined with liquid silicon infiltration (LSI) process. The results indicated that C/C–SiC composites present a better ablation resistance than C/C composites without doped SiC. The doped SiC and the ablation products SiO2 derived from it play key roles in ablation process. Bulk quantities of SiO2 nanowires with diameter of 80 nm–150 nm and length of tens microns were observed on the surface of specimens after ablation. The growth mechanism of the SiO2 nanowires was interpreted with a developed vapor–liquid–solid (VLS) driven by the temperature gradient.

In this essay the authors are seeking to examine a chemical surface activation process for NiP electroless plating of poly (ethylene terephthalate) (PET) films without using palladium catalyst, during which the nickel particles have been chelated with the C=O and COH groups of the carboxymethyl cellulose (CMC) on the PET film that are acting as a catalyst center for the electroless plating.

Through research of stiletto and analysis of cutting process of manual thermite cutting technology, mechanism and chemical compositions of cutting ammunition is expounded. This type of cutting ammunition was only operated in terms of some cutting technology, including cut method, cutting technique parameter, cutting operate. The chemical composition of the cutting ammunition is the key to the final incision quality. The powders include thermite, gas-making agents and alloying addition. KNO3 is up to 4.8% to 10.5% in the cutting medicament and CuO+Al is up to 13.6% to 22.8% in the thermite to cut steel of Q235 which is 263mm ×165mm × 20mm on the basis of the eject times of case primer, depth of the hole, diameter of the hole and the taper .

The carbon nanotubes with its stable structure, excellent mechanical properties, become the ideal enhancement phase of composite materials. The enhancement effect is affected by various factors, interface is one of the key factors determine its enhancement effect, also is the research focus of metal matrix composites. Briefly introduced carbon nanotubes reinforced aluminum matrix (CNTs/Al) composite material interface bonding mechanism and interface effect on the properties of composite materials, thermal expansion coefficient and preparation methods were reviewed, purity of carbon nanotubes and other factors impact on CNTs/Alcomposites interface, and puts forward the way to improve interface.

The paper presents a Fe-base manual SHS Welding material with CuO+Al and Fe2O3+Al being the thermit and adding ferroalloy materials for solving the problem of low mechanical properties of the manual SHS Welding joint. The structure and properties of the welded joint were studied. The results indicated that: the welding was fusion welding, and weld appearance is good. Cu-Fe alloy in the molten pool experiences liquid phase separation during rapid solidification, and the weld metal is macroscopically separated into one Fe-rich part and one Cu-rich part. Fe-rich phase is filled in the welding line. At the same time, tensile strength of the welded joint was close to 500 MPa, and impact toughness was close to 40J/cm2, and surface hardness was also close to HB350. It also indicated this technology can meet the need of repair of metal parts in field.