Daido Steel Co., Ltd.

Nissan Motor Company Limited

Koichiro Inoue

Takashi Yoshimoto

Jun Yoshida

Sadayuki Nakamura

Yoshio Okada

Kenji Sugiyama

Tomonori Miyazawa

Kazuhisa Ishida

Hidetoshi Satou

Wataru Naitou

Kouji Itakura

Noriyuki Shiwaku

Shinnosuke Yamada

Hideaki Ohtaka

Asako Kamimoto

The present invention relates to a metal powder containing: 0.001 mass %≤C≤0.45 mass %, 0.01 mass %≤Si≤3.50 mass %, Mn≤2.0 mass %, 7.5 mass %≤Cr≤21.0 mass %, 1.5 mass %≤Ni≤7.0 mass %, Mo≤1.3 mass %, 0.05 mass %≤V≤2.0 mass %, Al≤0.015 mass %, and N≤0.20 mass %, with the balance being Fe and unavoidable impurities, satisfying 0.05 mass %≤C+N≤0.58 mass %, and satisfying: 10<15C+Mn+0.5Cr+Ni<20 and Cr/Ni<5.6, where Cr=Cr+Mo+1.5Si+0.5Nb, and Ni=Ni+30C+30N+0.5Mn.

Metal powder

The present invention relates to a metal powder including 0.1&#x2264;C&#x2264;0.4 mass %, 0.005&#x2264;Si&#x2264;1.5 mass %, 0.3&#x2264;Mn&#x2264;8.0 mass %, 2.0&#x2264;Cr&#x2264;15.0 mass %, 2.0&#x2264;Ni&#x2264;10.0 mass %, 0.1&#x2264;Mo&#x2264;3.0 mass %, 0.1&#x2264;V&#x2264;2.0 mass %, 0.010&#x2264;N&#x2264;0.200 mass %, and 0.01&#x2264;Al&#x2264;4.0 mass %, with the balance being Fe and unavoidable impurities, and satisfying the following expression (1), 10&#x3c;15[C]+[Mn]+0.5[Cr]+[Ni]&#x3c;20 (1), in which [C], [Mn], [Cr] and [Ni] respectively represent the contents of C, Mn, Cr and Ni by mass %.

Disclosed is a non-heat treated steel for hot forging, particularly suitable for producing connecting rods of automobile engines. The steel consists essentially of: by weight, C: 0.3-0.8%, Si: 0.1-2.0%, Mn: 0.3-1.5%, P: 0.01-0.15%, Cr: 0-1.0%, V: 0-0.4%, Al: 0-0.05%, N: 0.005-0.03% and the balance being Fe and inevitable impurities, provided that the contents of C, Mn and Cr fulfill the following condition: 1.40[C %]+0.28[Mn %]+0.50[Cr %]&#x2267;0.75 Pearlite area fraction in this steel after hot forging is 50% or more. Notches are provided with laser beam on an intermediate part at the location from which fracture starts, and load is applied. Then, the intermediate is split to be two components (big end or cap and small end/rod for connecting rod). The components are adhered to form the parts.

Non-heat treated steel for hot forging with easy fracture splitting

Non-heat treated steel for soft nitriding

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Suita, Japan

Koichiro Inoue