Scholarlink

<p>18Ni (250 grade) maraging steel is a preferred material for rocket motor casings, welded by Auto-GTAW using a W2 filler wire (lean Mo, enriched Co). Following inadvertent use of base metal filler (M0), weldments produced with M0 and W2 fillers evaluated through radiographic assessment, Positive Material Identification (PMI), tensile testing, plane-strain fracture toughness (K<sub>IC</sub>) testing, microstructural characterisation, and microhardness mapping. M0 welds exhibited marginally higher tensile strength (~ 5%) but significantly lower fracture toughness (~ 19% reduction) compared to W2 welds, attributed to enhanced C14 Laves (Fe<sub>2</sub>Mo) phase formation and reverted austenite at grain boundaries. Radiography confirmed the loss of root bead contrast in M0 welds. PMI-based acceptance criteria using Co and Mo concentrations were established to screen affected weldments.</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

Effects of Filler Wire Composition on Weld Integrity: A Study on 18Ni Maraging Steel Weldments for Rocket Motor Casing

  • 期刊论文

  • 发表日期：

    2026年8月1日

查看全文
  • Gajanan R. Deshingkar,
  • Lagadu Yerrinaidu,
  • Goutam Nayak,
  • Sushant Manwatkar,
  • Chidanand Magadum,
  • Mayur Vaidya

摘要

18Ni (250 grade) maraging steel is a preferred material for rocket motor casings, welded by Auto-GTAW using a W2 filler wire (lean Mo, enriched Co). Following inadvertent use of base metal filler (M0), weldments produced with M0 and W2 fillers evaluated through radiographic assessment, Positive Material Identification (PMI), tensile testing, plane-strain fracture toughness (KIC) testing, microstructural characterisation, and microhardness mapping. M0 welds exhibited marginally higher tensile strength (~ 5%) but significantly lower fracture toughness (~ 19% reduction) compared to W2 welds, attributed to enhanced C14 Laves (Fe2Mo) phase formation and reverted austenite at grain boundaries. Radiography confirmed the loss of root bead contrast in M0 welds. PMI-based acceptance criteria using Co and Mo concentrations were established to screen affected weldments.