EFFECT OF MOLIBDENUM ADDITION AND HEAT TREATMENT ON CHARACTERISTICS OF TI-ZR-MO ALLOY

• Main Author: TANUWIJAYA, DIAN
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/21734
• Institution: Institut Teknologi Bandung

Metals and alloys have been widely used as biomedical materials. It is estimated that 70-80% of biomedical implants are produced from metal materials. Metal biomaterials such as stainless steels, Co-Cr alloys, pure titanium and alloys are widely used because of their excellent mechanical properties. But sometimes metallic materials exhibit properties that can be poisonous and can be broken due to corrosion and mechanical damage. The development of titanium-based alloys for biomaterial applications continues. This is due to the good application of titanium alloys in the field of biomaterials based on their mechanical, physical, and biological properties. The purpose of this study was to study the effect of the addition of molybdenum element and the provision of heat treatment to Ti-Zr-Mo alloys that contain no toxic elements for the human body. <br /> <br /> <br /> <br /> <br /> The experiment begins with the manufacture of button alloys by the arc-melting method. The resulting alloy blades consist of four variations of composition, ie Ti-25Zr, Ti-20Zr-5Mo, Ti-20Zr-10Mo, and Ti-20Zr-15Mo. Then cutting the sample button. Then the sample with the four compositions are given heat treatment in the form of aging and quenching. Aging is done at two different temperatures ie 750oC and 850oC for 1 hour. Four variations of sample composition were produced with three types of alloys, namely as-cast, 750oC aging, and 850oC aging. After that, each sample is done by observation and testing to know the micro structure, phase, hardness, and corrosion rate. The observation of microstructure is done by optical microscope. The formed phase is known through the results of X-Ray Diffraction analysis. The sample hardness was tested using the Vicker Hardness Test. The corrosion rate was obtained by testing using a potentiostat in a simulated body fluid ringer lactate solution. <br /> <br /> <br /> <br /> <br /> Based on experiments that have been done, the results showed that the level of molybdenum and also heat treatment very influential on Ti-Zr-Mo alloy properties. The addition of the molybdenum level can increase the stability of the beta phase in Ti-Zr-Mo alloys as seen from the increasing number of beta phases formed. At low Mo (Ti-20Zr-5Mo), heat treatment produces a martensite phase. While at high Mo content (Ti-20Zr-15Mo), heat treatment produces a metastable beta phase. The highest hardness value was obtained in alloys without the addition of Mo, ie Ti-25Zr, treated with 850oC aging heat then quenching, 811.8 HVN. The lowest corrosion rate value is obtained at the addition of Mo at 10% (wt.%) Of 0.000404 mm / year. <br />