Ali Nabeel, Lone Nadeem Fayaz, Siddiquee Arshad Noor, Imran Iffat, Haider Julfikar, Goyal Vipin, Puri Vrishin, Sardana Tushar
Department of Mechanical Engineering, Jamia Millia Islamia, New Delhi, 110025, India.
Manchester Metropolitan University, Manchester, M1 5GD, United Kingdom.
J Orthop. 2022 Aug 12;34:61-66. doi: 10.1016/j.jor.2022.08.012. eCollection 2022 Nov-Dec.
The need for bioresorbable implants that are able to dissolve within the body is rising, unlike their traditional counterparts. Bulk metallic glasses (BMGs) can perhaps serve this need, since they possess incredible properties, including high biocompatibility by virtue of their amorphous structure and absence of dislocations. However, the fabrication of BMGs is challenging, since, to achieve an amorphous structure, fast cooling is a pre-requisite which is very difficult to achieve for casting due to the fact that fast cooling rate and adequate rate of filling of the mold possess a trade-off relationship. Therefore, purpose of this work is to develop a simple novel hybrid approach that is cost effective and attempts to synthesize BMG based on Mg-Ca-Zn constituent. Synthesis of bioresorbable material was attempted by hybridizing friction stir processing (FSP) technique with gas tungsten arc welding (GTAW). FSP was performed with Magnesium as base material and Calcium granules as reinforcement. After FSP, GTAW process was performed by using Zn as filler material. The added Ca and Zn were found to effectively intermix with the Mg matrix in the FSP and GTAW steps, respectively. Especially, a relatively invariable distribution of Ca phases was observed in the stirred microstructure after FSP. Finally, a wide bead consisting of mixed dendritic and columnar cast structure was obtained. The current work is expected to alleviate the physiological issues pertaining to orthopaedic fixations and decrease the need for secondary surgeries in geriatric fractures.
与传统植入物不同,能够在体内溶解的生物可吸收植入物的需求正在上升。大块金属玻璃(BMG)或许可以满足这一需求,因为它们具有令人难以置信的特性,包括由于其非晶态结构和无位错而具有的高生物相容性。然而,BMG的制造具有挑战性,因为要获得非晶态结构,快速冷却是一个先决条件,而对于铸造来说这很难实现,因为快速冷却速率和模具的适当填充速率存在权衡关系。因此,这项工作的目的是开发一种简单新颖的混合方法,该方法具有成本效益,并试图合成基于Mg-Ca-Zn成分的BMG。通过将搅拌摩擦加工(FSP)技术与钨极气体保护焊(GTAW)相结合来尝试合成生物可吸收材料。以镁为基材、钙颗粒为增强体进行FSP。FSP之后,使用锌作为填充材料进行GTAW工艺。发现添加的钙和锌分别在FSP和GTAW步骤中有效地与镁基体混合。特别是,在FSP后的搅拌微观结构中观察到钙相的分布相对不变。最后,获得了由混合树枝状和柱状铸造结构组成的宽焊道。预期当前的工作将缓解与骨科固定相关的生理问题,并减少老年骨折二次手术的需求。