Correlation of parameters and microstructure of 3D printing bulk medical titanium-based metallic glass

Abstract

Metallic glass has developed over the past few decades. To fabricate the metallic glass, high cooling rates (105 K/s) is needed to form the disorder atomic structure [1]. Because metallic glass has no grain boundary, its characteristics are superior to traditional crystalline materials, such as good wear resistance, and excellent corrosion resistance [2]. In the past few decades, most amorphous alloy systems can only be manufactured to a millimeter size, causing the application difficulties [3]. Due to development of 3D printing technology nowadays, it’s expected to manufacture metallic glass in a larger size due to the localized melting process with a high cooling rate. Due to the breakthrough in size, it can be applied to medical equipment such as scalpels, dental implants, and various implants in the future. However, the relationship between the materials, 3D printing process parameter, and microstructure evolution is still needed to be explored. Thus, in study, such relationship of Ti-based metallic glass is studied through changing parameters of scan speed and laser power to vary cooling rates and microstructure by Selective Laser Melting (SLM). The samples were examined through the X-ray diffractometer (XRD) and the scanning electron microscope (SEM) with energy disthispersive spectrometry (EDS). The composition variation and microstructure evolution during the 3D printing process was discussed in detail from the point of view of 3D printing parameter, molten pool behavior, and heat of mixing. Furthermore, the mechanical properties of metallic glass were investigated by using micro-indentation, which results showed further that the microstructure indirect effects hardness and young’s modulus of the alloys.