To provide a steel material for machine structural use that is suitable for friction pressure welding, and in which part properties such as a fatigue strength and an impact strength are increased, and to provide a friction pressure welding part.
The steel material is produced by a specific rolling condition to have a specified composition containing a solid solution [V] and also to have a steel structure, wherein an average area ratio of ferrite grains to pearlite grains and a ferrite-pearlite area ratio, are a specific mixed-phase structure of specific fine ferrite grains and pearlite grains, so as to increase the part properties such as the fatigue strength and the impact strength of a composite steel material or composite steel part that is formed by joining the steel material to other steel materials by friction pressure welding.
MATSUGASEKO AKIHIRO
NAGAHAMA MUTSUHISA
| JP2008274393A | 2008-11-13 | |||
| JP2010007143A | 2010-01-14 | |||
| JPH10235447A | 1998-09-08 | |||
| JP2004360070A | 2004-12-24 | |||
| JP2008274393A | 2008-11-13 | |||
| JP2010007143A | 2010-01-14 | |||
| JPH10235447A | 1998-09-08 |
Seiji Kameoka
Hironori Takenaka
Toru Sakatani
Yoshiyuki Kaji
Makoto Suhara