Niu L.-B.,Shinshu University |
Nakada K.,Shinshu University |
Nakada K.,Nachi Fujikoshi Corporation
Corrosion Science | Year: 2015
The pitting corrosion behavior of 13Cr steel was investigated in simulated boiler waters containing chloride ions (Cl-) and sulfate ions (SO42-) using potentiodynamic and potentiostatic polarization tests in addition to pit morphology analysis. The presence of 100ppm Cl- in the water caused pitting corrosion of the steel. Pit initiation was inhibited by the addition of 50ppm or 100ppm SO42- into the water containing 100ppm Cl-. Pit growth was also suppressed by the presence of 50ppm SO42- in the water with 100ppm Cl-; however, it was conversely promoted in the presence of 100ppm SO42-. © 2015 Elsevier Ltd.
Shimatani Y.,Nachi Fujikoshi Corporation
Nihon Kikai Gakkai Ronbunshu, A Hen/Transactions of the Japan Society of Mechanical Engineers, Part A | Year: 2012
In order to study the effect of loading mode on fatigue properties of high speed steel (0.7C-4Cr-0.1W-3 Mo-2V) in very high cycle regime, fatigue tests under axial loading and rotating bending condition were performed in laboratory air using the hourglass shaped specimen. From the experiment results, clear duplex S-N curve appeared in both loading conditions, that is, there were two curves composed of a surface failure mode and a subsurface failure mode. Fatigue life under axial loading condition was shorter than that under the rotating bending condition, especially in low stress amplitude level. The difference in fatigue lifetime and transition of failure mode between the loading modes was discussed from the viewpoint of inclusion size, applied stress distribution across the specimen section and residual stress in surface layer. ©2012 The Japan Society of Mechanical Engineers.
Yasuoka M.,Tokushima University |
Yasuoka M.,Nachi Fujikoshi Corporation |
Wang P.,Tokushima University |
Murakami R.-I.,Tokushima University
Surface and Coatings Technology | Year: 2012
TiC xN 1-x single-layer (x=0-1.0) and TiC/TiC 0.5N 0.5/TiN multilayer coatings prepared using the hollow cathode discharge (HCD) ion plating method were investigated to improve the mechanical performance of high speed steel cutting tools. The carbon/nitrogen ratio of the TiC xN 1-x coating was controlled by adjusting the composition of an additional acetylene/nitrogen mixture gas during the ion plating process. The mechanical performance characteristics of the coated cutting tools, such as the surface hardness, adhesion, wear and dynamic hardness, were studied. The cutting tools coated by the multilayer films showed higher wear resistance and longer use life than those coated by TiC xN 1-x single-layer films. The higher dynamic hardness of the multilayer coatings was considered the primary contributor to the improvement of the mechanical properties. © 2011 Elsevier B.V.
NACHI FUJIKOSHI Corporation | Date: 2011-11-16
A drill capable of suppressing inter-layer peeling (delamination) while keeping hole diameter accuracy even if the number of holed to be worked increases is provided. The drill includes a first flank which has a ridge line forming a cutting edge, a second flank which is adjacent to the first flank and has a ridge line forming a land portion, and a third flank which is adjacent to the first flank and has a ridge line forming a chisel edge. The drill further includes a fourth flank which is surrounded by a ridge line forming the first flank, a ridge line forming the third flank, and a trough line forming the second flank
NACHI FUJIKOSHI Corporation and Toyota Jidosha Kabushiki Kaisha | Date: 2013-06-27
There is provided a manufacturing process of a battery equipped with a case and an electrode body having a positive electrode, a negative electrode and separators. The electrode body has an upper R portion and the respective separators have surplus portions. The case has an accommodation portion that has an opening in an upper face thereof and accommodates the electrode body, and a lid portion that closes up the opening in the upper face of the accommodation portion.