Papers in JOURNAL OF THE JAPAN SOCIETY FOR TECHNOLOGY OF PLASTICITY
(Vol.40 No.460 May 1999)
Ceramic Mechanical Seal for Rotary Joints Produced by
Shave-Joining Method
Keisuke KANNO, Takezo SASAKI,
Aranori HAYASHI and Terufumi MACHIDA
(Received on April 21, 1998)
Instead of expensive conventional bonding methods, a new manufacturing process
was developed for high-performance rotary joints, which are important elements
in machine systems to pass through oil and other liquors. The mechanical seal
of ceramics such as Al2O3, TiB2, SiC and Zr2O3 was shave-joined with austenitic
stainless steel housings for stators or rotors, and compared with a seal of
cemented carbide alloy. The joining temperature of steel ranges from 100 to 600,
and shaving depth is selected from values ranging from 0.15 to 0.5mm. As a
result of an endurance test the developed rotary joint was confirmed to possess
properties required for practical use:high joining strength, and good air tightness.
Key words : joining, shave-joining, ceramics, cemented carbide alloy, mechanical seals, rotary joint, joining strength, leakage test
Grain Size Predictions in Hot Forging of Vanadium
Microalloyed Steels
Zhe WANG, Tingquan LI, Akira KONO,
Nobuki YUKAWA and Takashi ISHIKAWA
(Received on May 20C 1998)
Empirical models combined with FEM simulation were developed to predict the
microstructure of hot forged vanadium microalloyed steel products. In order
to predict ferrite grain size, first, a hot upsetting test was conducted to
determine an empirical relationship between recrystallized grain size,
temperature and strain as well as a relationship between austenite grain size
and ferrite grain size. Secondly, an isothermal upsetting test was conducted
to investigate the relation between grain growth and holding time. These
empirical models were incorporated into FEM(DEFORM-2D). Ferrite grain size
for practical multiple stage hot forging was predicted. The results of the
predictions agree well with experimental results.
Key words : hot forging, microalloyed steel, FEM simulation,
recrystallized grain size, grain growth, austenite grain size, ferrite grain size