A sintered titanium alloy is composed of a titanium matrix or titanium alloy matrix and hard particles dispersed in the matrix, the sintered titanium alloy comprises: 4-8 mass % of aluminum (Al); 2-6 mass % of vanadium (V); 0.15-0.8 mass % of oxygen (O); at least one element selected from the group consisting of 0.2-9 mass % of boron (B), 0.5-3 mass % of at least one of molybdenum (Mo), tungsten (W), tantalum (Ta), zirconium (Zr), niobium (Nb), and hafnium (Hf), 0.05-2 mass % of at least one of Ia Group elements, IIa Group elements, and IIIa Group elements, 0.05-0.5 mass % of at least one of halogens; with the balance being titanium (Ti) and inevitable impurities. A method for economically producing a high-density sintered titanium alloy comprises mixing a raw material powder composed of a titanium powder and a powder for solid-solution hardening, rubbing and pressing the titanium powder before, during or after the mixing, so as to cause the raw material powder to have a desired tap density, compacting the mixed powder, and sintering the green compact under no pressure.

Sintered powdered titanium alloy and method of producing the same

High-density (98 pct TD) 95W-5Ti (wt pct) alloys have been fabricated by a combustion-synthesis-assisted hot explosive consolidation (CSA-HEC) technique. In the current procedure, a W + Ti powder compact is preheated by the heat released by a Ti + C exothermic combustion synthesis reaction and subsequently consolidated by pressure waves generated by the detonation of an explosive. The amounts of explosive charge, sample configuration, and molar ratio of exothermic material to sample were found to affect the degree of consolidation. Auxiliary temperature measurements were performed to determine the precompaction thermal history of the sample to obtain the optimum delay time for consolidation. As observed with scanning electron microscopy (SEM), the CSA-HEC microcomposites consist of W particles surrounded by a partially discontinuous Ti-rich matrix. Transmission electron microscopy (TEM) was also used to further characterize the W/Ti interfacial region. The pertinent features of the technique as well as those of the product microstructures are discussed.

Hot explosive consolidation of W-Ti alloys

The shock treatment of powders, for example, to increase defect density and activate sintering, or to density them to solid density has a relatively long history of application attempts in the area of advanced materials. Nevertheless, the scale of industrial fabrication is very small in comparison, not only with the traditional powder technology methods, but even in comparison with the explosive forming, welding, or explosive hardening, which use the same type of loading. There are two main reasons for this.

Advanced Materials Treatment by Shock Waves

This paper uses the explosive compaction method to produce Cu-matrix composites. The powders of Cu and WC were prepared by high-energy ball-milling. Experiments have been performed to compact powders of Cu and WC using cylindrical configuration. The results showed that the detonation velocity had effects on the density of the compacts. The effect has been detailedly studied. The compacted WC/Cu composites have been subjected to hot rolling. The microstructure, hardness, electrical conductivity and softening temperature of the composites have also been mentioned.

Research on Explosive Compaction Technology and Properties of WC/Cu Composites

Prealloyed Ti–6Al–2Sn–4Zr–2Mo titanium alloy powders made by a rotating electrode process were consolidated by three techniques: hot isostatic pressing (HIP), hot explosive compaction (HEC), and hot rolling (HR), to optimize the processing parameters in order to obtain fully dense compacts and the desired microstructures and mechanical properties. Room-temperature tensile properties show that all three techniques are capable of giving full density and mechanical properties equivalent to or better than wrought properties. Control of processing parameters which may require another step of deformation such as rolling gives more reliability for HIP and HEC compacts. Metallography and scanning electron microscopic studies on fractured tensile specimens revealed the presence of both metallic and non-metallic inclusions in the compacts. The control of such contaminations during manufacturing as well as processing is necessary for good mechanical properties. PM/0181

N. C. Birla

Papers

Consolidation of Prealloyed Ti–6Al–2Sn–4Zr–2Mo Spherical Powders