Titanium Hydride Powder Preparation Of Porous Titanium Process Research

Titanium and its alloys have a good biocompatibility, corrosion resistance and mechanical properties, So they have achieved great success in biomedicine applications and become a preferred medical metallic implant materials for people. According to the characteristics of human bone was porous, If we use the porous structure of titanium and its alloys as a implant material. Not only can reduce their elastic modulus to improve the biocompatibility, But also conducive to tissue ingrowth, nutrition and transportation to improve implant material biological activity.Powder metallurgy method was simple process, full utilization to row material and low cost of raw materials. Currently, Mostly used titanium powder as the raw materials of PM. It has high cost, high content of oxygen and so on. At 300℃,Titanium hydride powder was more stable and not easily react with oxygen, According to the titanium powder and titanium hydride powder characteristics, In this paper, we used titanium hydride powder as base metal raw material, ammonium bicarbonate as pore. A controlled pore structure of porous titanium preparated by cold isostatic pressing-Fabrication, We mainly studied the formation of porous titanium and pore characteristics with the technological conditions of the preparation of porous titanium and the properties of the porous titanium with different process conditions. lastly determined the appropriate technology parameters of prepara-tion of porous titanium.Experimental results show that the forming pressures, sintering temperatures and the addition of the pore volume of the porous were the main factors to the pore structure, thus the key process of the porous structure is forming, sintering and the addition of the pore volume of the porous. When the molding pressures were 60MPa,80MPa,100MPa,120MPa, 140MPa, the porosity of the porous titanium were 20.6%,19.1%,17.4%,16.9%,16.6%, respectively. And with the pressure increased, the corresponding linear shrinkage deceased; sintered temperature has a major impaction to the physical properties of the porous titanium, when the sintered temperature increases, the linear shrinkage rate increased, The shape of holes changed from the shape of irregular shape to the shape of gradually, and the pore structure was best at 100MPa with 950℃sintered 5 h. To increase the porosity and pore size,we added pore-forming agent, the porosity of the porous titanium were 17.4%,32.4%, 44.6% and 50.5% respectively, when we added the pore amount of NH4HCO3 0%,10%, 20%,30%. And found the average pore size increased with the pore amount added. The pore sizes range were between 10μm and 300μm.In the compression test, The stress-strain curves of the specimen showed for the three-stage deformation(Elastic deformation,Plastic deformation and fracture). The mechanical properties and energy absorption properties of the porous titanium were greatly as the preparation conditions. the corresponding yield strength were 331.9 Mpa; 208.1Mpa;93.4 Mpa;72.9Mpa and the corresponding elastic modulus were 12.95GPa; 6.48GPa;4.45GPa;3.01GPa,respectively, with the pore dosage of 17.35%,32.39%, 44.57% and 50.47% NH4HCO3. They meet the weight-bearing implants Body require-ments in the mechanics; The energy absorption capacity and absorption efficiency were changed with the process parameters changed. The pore was the lagest impaction, The worse energy absorption capacity with the more pore dosage.