ORIGINAL ARTICLEMachining of biocompatible materials: a reviewKushendarsyah Saptaji 1 & Mebrahitom Asmelash Gebremariam 1 & Mohd Azmir Bin Mohd Azhari 1Received: 11 September 2017 /Accepted: 2 April 2018# Springer-Verlag London Ltd., part of Springer Nature 2018AbstractThe need for more effective and efficient manufacturing processes to transform the biocompatible materials into high standardartificial human body components (implants) is rapidly growing. Machining of biocompatible materials as one of the keyprocesses in manufacturing of implants need to be improved due to the significant effects of machined surface quality to thecompatibility and osseointegration with human organs such as tissues, bones, and environment of the human body. The chal-lenges of machining biocompatible materials due to their applications as bio-implants in the human body and the nature ofmaterials properties and microstructures have been explored and solved by various researchers. This article reviews the trendsand developments of the machining of biocompatible materials. A range of possible machining technologies and strategies onvarious biocompatible materials using conventional (milling, turning and drilling) and non-conventional or advanced (abrasivewaterjetmachining(AWJM),ultrasonicmachining(USM),ionbeammachining(IBM),laserbeammachining(LBM),electricaldischarge machining (EDM), and electron beam machining (EBM)) are presented and discussed. This review also examines theemerging new technologies such as additives manufacturing and hybrid processes as potential solutions and future researchtrends in order to fulfill the high standard requirements for a wider range of applications of the biomaterials.Keywords Biocompatiblematerials . Machining . Machinability . Conventionalmachining . Advancedmachining . Micro-scalemachining . Finiteelementanalysis . Additivemanufacturing1 IntroductionThe demand for biomedical implants is rapidly growing inorder to improve the quality of human life. The bio-implantsare mainly the bio-mimicry of natural and artificial biomate-rials used for body components. Such artificial components(implants)can beusedfor a shortperiodoftime, long-term,oreven permanent in the biological tissue if not removed surgi-cally [1]. Currently, implants are being used in many differentparts of the body for various applications such as orthopedics,pacemakers, cardiovascular stents, neural prosthetics, or drugdelivery system [2, 3]. The biomedical components such asshown in Fig. 1 generally must have good corrosion resis-tance, suitable surface properties, sufficient mechanicalstrength, biocompatibility with tissues and bones, naturallydegraded and disappeared in tissue, and also reliable chemicalstability and safety [4]. The materials selections and designhave significant effects on the implant lifespan [3].In this case, metallic alloys such as stainless steel, titaniumand its alloys, cobalt–chromium alloys, nickel–titanium shapememory alloys, and magnesiumalloysare the mostpreferablebiomaterials. Though ceramics and polymers can also be usedasanimplantssuchasinthe artificialhipjoints[5].Ingeneral,the ceramic and polymer implants are used individually orassembled with other metallic materials. Titanium and its al-loys are widely used in joints replacement, spine and traumasystems, dental implants, and pacemaker casings. Magnesiumandits alloysare alsopotentialmetallicmaterialstobeusedasadegradableimplantmaterialsbecauseitislessexpensive[4].It is known that magnesium is an essential element of thehuman body and naturally found in bone tissues and harmlessexcreted in the urine. However, magnesium is known for itslow corrosion resistance especially in saline media that is anenvironmentofthe human body. Inorder toalter the corrosionresistance, surface and subsurface qualities of machinedmagnesium alloys are normally improved using addi-tional finishing processes such as electrical discharge ma-chining (EDM), electrical chemical machining (ECM), anddeep rolling [6].* Kushendarsyah Saptajikushendarsyah@ump.edu.my1Faculty of Manufacturing Engineering, Universiti Malaysia Pahang,Pekan, Pahang, MalaysiaThe International Journal of Advanced Manufacturing Technologyhttps://doi.org/10.1007/s00170-018-1973-2
