減圧気中のアーク溶接現象に関する研究(第3報)

• 山本 利雄

  三菱電機(株)中研

• 島田 弥

  三菱電機(株)中研

書誌事項

タイトル別名

• A Study of the Arc Welding Phenomena at Reduced Gas Pressures (Report 3)
• Penetration Formed by the Fixed TIG Arc in the Metal Specimen
• 固定TIGアークによる各種金属材料の溶込み

抄録

Various penetration shapes formed in the plates of copper, aluminum, mild steel and stainless steel by the fixed TIG arc at reduced argon pressures are discussed in relation to the electrical and thermal characteristics of the arc mentioned in the previous reports, where the arc is formed between the 2% thoriated tungsten cathode of 4 mm in diameter shaped like a pencil form and a directly or indirectly water cooled anode plate under the following conditions.<BR>Gas Pressure : 18 to 760 mmHg<BR>Arc Current : 250, 400, 450A<BR>Arc Length (Distance between Electrodes) : 4, 9, 15, 25 mm<BR>The facts elucidated are as follows<BR>(1) At reduced gas pressure, "cathode zone" (a bright spherical zone) is observed at the neighborhood of the cathode. When the cathode zone touches the anode specimen, the contact zone on the anode surface melts rapidly and a large "conduction type penetration" is formed in the specimen. Then the cathode zone is presumed to have a higher energy density compared to the arc column.<BR>(2) In the specimen of low thermal conductivity, the "peripheral type penetration" is formed due to the convectional flow in the molten pool when the energy density of the arc is considerably high. It happens sometimes that the depth of the conduction type penetration formed at small current is deeper than that of the peripheral type penetration of larger current.<BR>(3) At higher pressure the molten pool beneath the arc depresses and the "finger type penetration" is formed in this case. For directly water cooled specimen, the shape of the molten pool is conserved down to room temperature and a hollow part is often formed when the arc length is sufficiently long. At the bottom of the hollow part a solid surface is exposed and no solidified layer is observed on it.<BR>(4) The, penetration in low thermal conducters such as mild steel and stainless steel varies from the "conduction type" to the "peripheral type" and further to the combined type of "peripheral type" and "finger type", with an increase in the energy density and the plasma stream at the specimen surface.<BR>For high thermal conductors like copper and aluminum, the "conduction type" is easily formed by the thermal conduction mechanism. Although the "finger type" is likely to appear when the arc energy density is considerably high, no "peripheral type" penetration is observed.

収録刊行物

• 溶接学会誌

  溶接学会誌 39 (11), 1171-1179, 1970

  一般社団法人 溶接学会

キーワード

• Metals and Alloys
• Surfaces, Coatings and Films
• Mechanical Engineering
• Mechanics of Materials

詳細情報

• CRID: 1390282681479040640
• NII論文ID: 130003763129
• DOI: 10.2207/qjjws1943.39.11_1171
• ISSN: 18837204
• ISSN: 00214787
• 本文言語コード: ja
• データソース種別:
  • JaLC
  • Crossref
  • CiNii Articles
• 抄録ライセンスフラグ: 使用不可