| Platinum and platinum alloy has good high temperature resistance, corrosion resistance, make the platinum materials are widely used in various industries.But due to the low pure platinum room temperature strength, its limited industrial application. Vacuum arc melting was prepared by two different alloys, titanium content namely Pt-Ti1.5, Pt-Ti2.0.By analyzing XRD, TEM obs ervation of platinum titanium alloy after heat treatment deformation of organization, and then measure its mechanical properties under different condition.Research shows that:(1) By XRD and TEM detection analysis confirmed that the precipitation of Pt8Ti, critical temperature TC is about 800℃.The diffuse distribution in the matrix, and occupy large volume fraction,the dislocation cut ordered phase Pt8Ti particles will have a antiphase domain boundary (APB), hinder of the dislocation movement occurs, which makes the system energy increases, resulting in alloy strengthening.(2) Pt-Ti alloy solid solution strengthening effect is significant, the alloy can markedly improved the hardness, as a result of the Pt-Ti2.0 solute ratio relative to the concentration of the Pt-Ti1.5 is bigger, so the solid solution strengthening effect is slightly higher than the latter, which is 183.7 HV and 159.8 HV.Compared with the pure Pt 58 hv hardness, increased by 271% and 174%.(3) Two kinds of alloy after solid solution treatment for aging treatment, respectively, for Pt-Ti1.5 alloy in the aging process when the processing conditions of 500℃* 5 h,239.8 HV, maximum hardness value relative to the hardness of the solid solution state 49% improvement;For Pt -Ti2.0 alloy aging in the process of their process conditions of 500 ℃ * 3 h maximum hardness value, the corresponding hardness value of 252.9 HV;For the precipitation of the ordered phase alloy strengthening effect is obvious.(4) When alloy solid solution-cold rolling processing, two kinds of alloy of hardness values are increased with the increase of deformation linear increase, when after 90% cold deformation, hardness value is 269.1 HV and 295.7 HV, strain hardening effect is obvious.(5) After solid solution-cold rolled alloy in 200～1100℃ annealing treatment, alloy of Pt-Ti1.5 under the condition of 300 ℃ 1 h hardness value maximum is 347.4 HV, the alloy showed low temperature annealing hardening effect; Pt-Ti2.0 alloy in 300～800 ℃ annealing temperature range are showed high hardness value, when the alloy at 300 ℃ annealing hardness value maximum 407.9 HV, hardness values are within the range of 400 ～800℃and with hardness which is 395 ±5 HV, showed good thermal stability, due to the precipitation of ordered phase Pt8Ti for caused by dispersion strengthened alloy, then alloy hardness to reduce when with a rise of temperature.(6) For selection of alloy samples stretched and electrical performance test, both kinds of alloy showed high tensile strength and good conductivity, Pt-Ti1.5 alloy maximum tensile strength is in solid solution+cold rolled+300℃after annealing treatment, the tensile strength of 1000 mpa, while the corresponding lower elongation, as its resistivity minimum is 35.9 nu Ω. Cm, its solid solution state tensile strength is 520 Mpa, elongation reached to 11.7%; Pt-Ti2.0 alloy tensile strength is the largest after solid solution+cold rolling+800℃ anneling process of 960 Mpa, while the elongation is low, the resistance of the corresponding rate of 35.6 μΩ. cm, the solid solution state expands rate of 9.8%, tensile strength is 570Mpa;In summary, solid solution strengthening, solid solution aging strengthening, strain hardening and platinum alloy after annealing can obviously improve the mechanical properties, and when the titanium content is 2.0% wt, produced in the process of annealing and aging of the ordered phase Pt8Ti can effectively restrain of softening annealing process, and the performance of the alloy after heat treatment deformation is obviously improved, so for the extension of platinum extremely has the potential value in actual application.
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