Dissimilar friction welding of titanium alloy and stainless steel and its welding principle elucidation for spinal fixation application

脊柱固定应用钛合金与不锈钢异种摩擦焊及其焊接原理阐明

• 批准号: 20K05169
• 负责人: 劉 恢弘
• 金额: $ 2.75万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2020
• 资助国家: 日本
• 起止时间: 2020-04-01 至 2022-03-31
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-20K05169/
• 关键词: Friction welding; Titanium alloy; Stainless steel; Ultralow rotation speed; High friction pressure; Microstructure; Mechanical properties; Microstructural; Welding principle; Spinal fixation surgery

In the last step, we have found that high shear strain rate between two materials and high temperature rising rate would cause the formation of harmful mechanically mixed layers during friction welding (FW) of Ti-6Al-4V (Ti64) and SUS316L, hence significantly deteriorating the joint quality. Rotation speed reduction (to 100 rpm) and liquid CO2 cooling were then adopted to reduce the shear strain rate and temperature rising rate. As a result, the mechanically mixed layer formation was effectively suppressed, and the joint quality was successfully improved.Based on these findings, an ultralow rotation speed with a proper high friction pressure were adopted in this step in order to eliminate the liquid CO2 cooling process. The ultralow rotation speed of 40 rpm provided a low temperature rising rate and a low peripheral velocity corresponding to a low shear strain rate between faying surfaces, hence suppressing the formation of harmful mechanically mixed layers and associated cracks. The proper high friction pressure of 450 MPa produced a proper welding temperature that produced a thin and strong　intermetallic compound layer while avoiding interface cracking. Furthermore, the proper high friction pressure worked to guarantee a sufficient faying surface deformation on SUS316L to sufficiently reduce surface roughness, break oxide layers and create fresh surfaces. Finally, a Ti64/SUS316L FW joint with superior quality was successfully fabricated in a simpler way using ultralow rotation speed and proper high friction pressure, without using liquid CO2 cooling.

在最后一步中，我们发现两种材料之间的高剪切应变速率和高的温升速率会导致Ti-6Al-4V（Ti64）和SUS 316L摩擦焊接（FW）过程中形成有害的机械混合层，从而显著恶化接头质量。然后采用转速降低（至100 rpm）和液体CO2冷却来降低剪切应变速率和升温速率。在此基础上，采用超低转速和适当的高摩擦压力，消除了液态CO2冷却过程，有效地抑制了机械混合层的形成，提高了接头质量。40 rpm的超低转速提供了对应于接合表面之间的低剪切应变率的低温度上升速率和低圆周速度，因此抑制了有害机械混合层和相关裂纹的形成。适当的450 MPa的高摩擦压力产生适当的焊接温度，产生薄而强的金属间化合物层，同时避免界面开裂。此外，适当的高摩擦压力可以确保SUS 316L的接合面充分变形，以充分降低表面粗糙度，破坏氧化层并产生新的表面。最后，在不使用液态CO2冷却的情况下，采用超低转速和适当的高摩擦压力，以一种简单的方法成功地制备出了具有上级质量的Ti 64/SUS 316 L FW接头。

项目成果

Dissimilar friction stir welding of pure Ti and carbon fiber reinforced plastic

纯钛与碳纤维增强塑料异种材料搅拌摩擦焊

• 发表时间: 2020
• 作者: Jeong-won Choi;Yoshiaki Morisada;Huihong Liu;Kohsaku Ushioda;Hidetoshi Fujii;Kimiaki Nagatsuka;Kazuhiro Nakata
• 通讯作者: Kazuhiro Nakata

テーパー試料形状を利用した中炭素鋼における圧力制御通電圧接

使用锥形样品形状的中碳钢压力控制载流连接

• 发表时间: 2021
• 作者: 劉 恢弘;宮垣 徹也;釜井 正善;馬 運五;麻 寧緒;藤井 英俊
• 通讯作者: 藤井 英俊

Superplastic deformation mechanism of the friction stir processed fully lamellar Ti-6Al-4V alloy

• DOI: 10.1016/j.msea.2020.139390
• 发表时间: 2020-05
• 期刊: Materials Science and Engineering A-structural Materials Properties Microstructure and Processing
• 影响因子: 6.4
• 作者: Wenjing Zhang;Huihong Liu;H. Ding;H. Fujii

Fabrication of High-Quality Joint in Dissimilar Friction Welding of Ti-6Al-4V Alloy and SUS316L Stainless Steel

Ti-6Al-4V合金与SUS316L不锈钢异种材料摩擦焊高质量接头的制作

• 发表时间: 2021
• 作者: H. Liu;Y. Aoki;Y. Aoki and H. Fujii
• 通讯作者: Y. Aoki and H. Fujii

ジュール熱大荷重局部変形接合法を利用した高炭素鋼の低温圧接：界面組織観察と接合機構解明

采用焦耳加热大载荷局部变形连接方法的高碳钢低温焊接：界面组织的观察和连接机理的阐明

• 发表时间: 2020
• 作者: 劉 恢弘;宮垣 徹也;釜井 正善;馬 運五;麻 寧緒;藤井 英俊
• 通讯作者: 藤井 英俊