Clarification of Guideline to Optimization of Joining Conditions to Control the Interface of Dissimilar Material Joints obtained Friction Stir Spot Welding

2023 Fiscal Year Final Research Report

• Project/Area Number: 20K05121
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 26030:Composite materials and interfaces-related
• Research Institution: Okinawa National College of Technology
• Principal Investigator: Tsumura Takuya 沖縄工業高等専門学校, 機械システム工学科, 准教授 (00283812)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: 難燃性マグネシウム合金 / めっき鋼板 / ツール位置制御接合 / ツール荷重制御接合 / 接合中ツール荷重 / 接合中ツール側温度 / 接合中材料側温度 / 引張せん断強度

Outline of Final Research Achievements

In the friction stir spot welding (FSSW) of flame-retardant magnesium (Mg) alloy and plated steel sheet, (1) a measurement system for in-process measurement (measurement during the welding process) was established, and (3) the effects of welding conditions on in-process measurement and joint strength were examined. In addition, a comparative study of the dissimilar metal weldability of the two methods was conducted using two types of equipment with different control methods. On the other hand, (2) the effects of tool shape and material on in-process measurement and joint strength, and dissimilar metal FSSW of flame-retardant Mg alloy and titanium (Ti) alloy were not conducted, and therefore it was not possible to extract welding conditions (tool shape and material, welding conditions) for joint interface control or obtain optimization guidelines.

Free Research Field

溶接・接合工学

Academic Significance and Societal Importance of the Research Achievements

難燃性マグネシウム合金とめっき鋼板・チタン合金との摩擦攪拌点接合（FSSW）に関する報告、並びに異種金属のFSSW接合において、接合条件が接合工程中の計測量と継手強度に及ぼす影響の検討に関する報告のいずれも見当たらない。また、ツール挿入量の制御方式間、特に異種金属の接合における相互比較を行った例は見当たらない。本研究は、異種金属のFSSW接合の機構解明だけでなく、新たに開発されつつある軽合金と異種材料接合によるそのマルチマテリアル化などへのFSSWの適用範囲拡大に寄与する。また輸送機器軽量化により、エネルギー消費量やCO2排出量の削減に貢献し、SDGsの観点から波及効果は極めて大きい。