PENGARUH SANDBLASTING DAN ELECTROPOLISHING TERHADAP KEKASARAN PERMUKAAN, STRUKTUR MIKRO, DAN KEKERASAN SEKRUP IMPLAN BAJA TAHAN KARAT AISI 316L

• Main Authors: , MUH. IQBAL M, , Muslim Mahardika, S.T., M.Eng., Ph.D
• Format: Theses and Dissertations NonPeerReviewed
• Published: [Yogyakarta] : Universitas Gadjah Mada 2012
• Subjects: ETD
• Online Access: https://repository.ugm.ac.id/100947/; http://etd.ugm.ac.id/index.php?mod=penelitian_detail&sub=PenelitianDetail&act=view&typ=html&buku_id=57414
• Institution: Universitas Gadjah Mada

Sandblasting is a method for improving the surface hardness and improving surface roughness of a material while the electropolishing process is an electrochemical erosion method of the surface. Mechanical properties of 316L stainless steel implants screw which is still vulnerable to cracks on the surface can be improved by applying the combination of both sandblasting and electropolishing methods.The purpose of this study is to see the effect of hardness, microstructure, and surface roughness of the 316L stainless steel implant screw. Roughness and hardness testing of the screw implant was carried out by applying the sandblasting method, electropolishing method, and a combination of both methods.Sandblasting process was carried out by turning the screws implant inside the sandblasting box and blasting using silica sand. The size of the silica sand used was between 725 to 1.475 μm and the nozzle distance toward the screw was 88 mm with the blasting pressure was 5-7 kg/cm2.Electropolishing equipment was using a DC current.There were several variations of the time, voltage, and electrode spacing in that electropolishing process.Electrolyte solutions which were used consist of sulfuric acid (H2SO4) and phosphoric acid (H3PO4) with a ratio of 1:1. The result shows that the sandblasting process can increase the hardness up to 25% and roughness up to 54%. Electropolishing result can reduce the surface roughness. Roughness screw after machining Ra 0.679 μm is down to Ra 0.095 μm. The combination process which is carried out to a screw implants are still experiencing an increase in hardness up to 20% and a decrease in roughness due to electropolishing process.