キーホールの端に移動するクリティカル不安定は,レーザーメルトで多孔性を生成
Cang Zhao1,2, Niranjan D Parab3, Xuxiao Li4
1Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China. cangzhao@tsinghua.edu.cn rollett@andrew.cmu.edu ts7qw@virginia.edu.
Science (New York, N.Y.)
|November 27, 2020
まとめ
メタル3Dプリントの鍵穴の毛穴は 溶融池の不安定性によって引き起こされます この不安定性によって発生する 音波は 孔を鍵穴から遠ざけて 欠陥を形成します
科学分野:
- 材料科学
- アディティブ製造
- 金属の物理
背景:
- レーザー粉床融合 (LPBF) は,金属の重要な添加物製造技術である.
- 毛穴の欠陥,特に鍵穴の毛穴は,LPBFコンポーネントの疲労性能を制限する.
- 鍵穴の毛穴は,特定の高電力,低スキャンのレーザー処理条件下で形成されます.
研究 の 目的:
- Ti-6Al-4VのLPBF中の鍵穴の動的形成メカニズムを調査する.
- 溶融池の不安定性による 毛穴の形成と捕獲の役割を明らかにする.
- 鍵穴の多孔性に対するパワー・スピード・レジムの境界を特徴付ける.
主な方法:
- 高速のX線画像を用いて,毛穴の形成を観察した.
- 鍵穴のダイナミクスを分析し 溶融池の動作をレーザーで処理した
- 異なるレーザーパワーとスキャン速度の条件下でTi-6Al-4Vの毛穴の進化を調べた.
主要な成果:
- 鍵穴の先端の不安定性が 毛穴の形成の源だと判明した
- 不安定によって発生した 音波が鍵穴から 毛穴を遠ざける
- パワー・スピード空間における鍵穴の多孔性体制の鋭い,滑らかな境界を決定し,裸板と粉末床条件に一貫した.
結論:
- 鍵穴の不安定性は,LPBFの毛穴形成の主な要因である.
- 溶融池内の音波は 毛穴を欠陥として閉じ込めることに 重要な役割を果たします
- このダイナミクスを理解することで 添加材料で製造された金属部品の 孔隙性を軽減する戦略を 策定することができます
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