Scholarlink

<p>Laser powder bed fusion (LPBF) imposes steep thermal gradients, resulting in distortion and the formation of significant residual stresses, which often precipitate in-situ cracking at support interfaces and sharp geometric features. To isolate their influence on structural integrity, we combined fracture mechanics testing with residual stress evaluation on as-built compact tension specimens printed in two orthogonal orientations. The experimentally measured apparent stress-intensity factor was deconvolved into mechanical and residual-stress components, yielding a residual-stress-free fracture toughness (<InlineEquation ID="IEq1"> <EquationSource Format="TEX">\({K}_{ICeff}\)</EquationSource> <EquationSource Format="MATHML"><math> <msub> <mi>K</mi> <mrow> <mi mathvariant="italic">ICeff</mi> </mrow> </msub> </math></EquationSource> </InlineEquation>). Apparent fracture toughness (<InlineEquation ID="IEq2"> <EquationSource Format="TEX">\({K}_{IC})\)</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <msub> <mi>K</mi> <mrow> <mi mathvariant="italic">IC</mi> </mrow> </msub> <mrow> <mo stretchy="false">)</mo> </mrow> </mrow> </math></EquationSource> </InlineEquation> ranged from 25 to 35&#xa0;MPa&#xa0;m<sup>1/2</sup>, whereas <InlineEquation ID="IEq3"> <EquationSource Format="TEX">\({K}_{ICeff}\)</EquationSource> <EquationSource Format="MATHML"><math> <msub> <mi>K</mi> <mrow> <mi mathvariant="italic">ICeff</mi> </mrow> </msub> </math></EquationSource> </InlineEquation> increased to 45–52&#xa0;MPa&#xa0;m<sup>1/2</sup>. Residual stresses, therefore, depress the material’s residual-stress-free resistance by up to ~ 50% and accentuate orientation-dependent anisotropy. The framework presented offers a route for quantifying process-induced toughness degradation in LPBF alloys.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

The effect of residual stress on the fracture toughness of Ti–6Al–4V produced by laser-based powder bed fusion

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2026年1月12日

查看全文
  • D. F. Louw,
  • M. Neaves,
  • T. H. Becker

摘要

Laser powder bed fusion (LPBF) imposes steep thermal gradients, resulting in distortion and the formation of significant residual stresses, which often precipitate in-situ cracking at support interfaces and sharp geometric features. To isolate their influence on structural integrity, we combined fracture mechanics testing with residual stress evaluation on as-built compact tension specimens printed in two orthogonal orientations. The experimentally measured apparent stress-intensity factor was deconvolved into mechanical and residual-stress components, yielding a residual-stress-free fracture toughness ( \({K}_{ICeff}\) K ICeff ). Apparent fracture toughness ( \({K}_{IC})\) K IC ) ranged from 25 to 35 MPa m1/2, whereas \({K}_{ICeff}\) K ICeff increased to 45–52 MPa m1/2. Residual stresses, therefore, depress the material’s residual-stress-free resistance by up to ~ 50% and accentuate orientation-dependent anisotropy. The framework presented offers a route for quantifying process-induced toughness degradation in LPBF alloys.