Influence of the sintering temperature on the microstructure, mechanical properties and densification characteristics of (TiB+TiC)/TC4 composite

A hybrid of TiB whiskers and TiC particles reinforced TC4 matrix composites were in-situ synthesized by spark plasma sintering (SPS) using a TC4-0.6wt.% B4C powder mixture at temperatures range from 550°C to 1150°C. The effect of sintering temperature on microstructure, grain size, mechanical properties and densification process of the (TiB+TiC)/ TC4 matrix composites were investigated. The composite sintered at 1050℃ has the highest tensile strength (1129.0 MPa), yield strength (1077.8MPa) and plasticity (7.1%). The aspect ratio of TiB whiskers increases almost linearly below 1050°C and its highest value is 33.2. The grain size of TiC increases with the increase of sintering temperature, and rapid growth occurs in the range of 850°C to 950°C. The composite sintered body appears four shrinkage stages before applying sintering pressure. The corresponding peak temperatures are 663℃, 758℃, 840℃ and 994℃, respectively.

Wear and Residual Stress Analysis of Waste Sea Shell and B4C Particles Reinforced Green Hybrid Aluminium Metal Composite

Present work, evaluates the effects of Sea shell and B4C powder on the mechanical behavior of the aluminium material (Al 6082). Stir casting method was used to fabricate a hybrid composite of Al 6082 with sea shell and B4C. A linear reciprocating tribometer was used to evaluate the wear and friction behavior. The addition of sea shell and B4C particles, resulted in 7-13 % reduction in coefficient of friction and 32-43 % improvement in wear resistance as compared to the Al 6082 alloy. The average Vicker hardness was also improved by 20-70 %. The residual stresses developed during the mechanical testing were also measured to inspect the generation of residual stresses in the fabricated composite. Optical micrographs and scanning electron microscope (SEM) were obtained to analyze the prepared composites for the wear behavior. Waste sea shells were reinforced with B4C in Al 6082 alloys. Microhardness along with microstructure and residual stress of the developed green hybrid aluminium metal composite are compared and presented. The wear and friction data have also been shown in this paper for the use of green hybrid aluminium composite in tribological applications.

Pulsed-PTA Preparation of B4C-Based Titanium Matrix Cermet

Pulsed plasma transferred arc surfacing is presently used in many industrial applications to make protective layers against corrosion, temperature exposition, and excessive wear. Increasing wear resistance is especially important in areas of industry where titanium alloys are used, such as aviation and cosmonautics, because the wear resistance of titanium alloys is often weak. One way to increase the wear resistance is to deposit or form a cermet with a titanium matrix (TMC) on the surface of the part. The present study deals with the fabrication and characterization of TMC based on B4C. TMC with B4C was formed by cofeeding Ti6Al4V and B4C powder into a melting pool. It has been found that the deposited, relatively thick layers have homogeneously dispersed B4C grains in the matrix. The deposits are metallurgically connected to the substrate - Ti6Al4V. The TMCs were investigated in terms of microstructure and chemical composition. Wear resistance was determined using the linear pin test.

Laser Surface Modification of Aluminium Alloy AlMg9 with B4C Powder

This paper presents the effects of laser treatment (fiber laser YLS-4000) on the microstructure and selected mechanical properties of the surface layer of AlMg (AlMg9) foundry alloy obtained by alloying with boron carbide (B4C). The correlation between laser alloying process parameters and selected properties of the formed layer was discussed. The studies were supported by microstructural analysis of the remelted zone (RZ), heat affected zone (HAZ), undissolved carbide particles, substrate material, and precipitates formed during rapid solidification. Metallographic investigations of the laser-treated layer were performed using optical microscopy and scanning electron microscopy (SEM). The elemental composition and a detailed analysis of chemical composition in micro-areas were carried out using energy dispersive X-ray spectroscopy (EDS). The remelting thickness, heat-affected zone (HAZ), and amount of base material in surface layers were determined. Microhardness tests were performed on transverse cross-sections of the remelted zone to obtain the hardness profiles in the base material (BM), remelted zone (RZ), and heat affected zone (HAZ). The hardness, roughness, and wear resistance measurements showed that the highest tribological properties of the obtained surface layer were achieved using 0.5 Bar protective gas (Ar) during alloying with B4C powder.