Kozo Tsunoyama

Spot Weldability and Fatigue Property of Hot-Rolled High-Strength Sheet Steels for Wheel Usage

Spot weldabilities and fatigue properties of hot-rolled high strength sheet steels for wheel use, with tensile strength of 45 to 60 kgf/mm 2 were investigated. The specimens used were phosphorus-niobium bearing steel (P-Nb steel), phosphorus-manganese bearing steel (P-Mn steel) and conventional carbon-manganese bearing steel (C-Mn steel). The P-Nb steel and the P-Mn steel have been developed by the authors for wheel rim use and wheel disc use, respectively

Application of SIMS to Analysis of Steels

The mechanical and chemical properties of steels are largely influenced by the concentrations and distributions of impurity elements. A variety of analytical techniques have been applied to analysis of these elements, and it has been proven that secondary ion mass spectrometry (SIMS) is one of the most useful. SIMS has great sensitivity with excellent lateral resolution and can accomplish surface analysis. These capabilities make SIMS a unique technique for solving several metallurgical problems such as corrosion, passivation, toughness and brittleness. The present paper is a brief review of studies performed in our laboratory using an IMMA made by Applied Research Laboratories.

Sputtering of Metals with 20 keV O 2 + ; Characteristic Etch Patterns, Sputtered Atom Yields and Secondary Ion Mass Spectra

In secondary ion mass spectrometry an oxygen primary beam is frequently used because it enhances and stabilizes the yield of secondary sample ions [1,2]. But its role in the process of secondary ion emission is not yet fully understood [3–6].The purpose of the present paper is to investigate the surface structure, sputtered atom yields and secondary ion mass spectra of metals bombarded with O2 +. Accumulation of these fundamental data will help to elucidate the effect of oxygen ion on sputtering and to establish the method of quantitative interpretation of mass spectra.

Quantitative Analysis of Zn-Fe Alloy Electrodeposit on Steel by Secondary Ion Mass Spectrometry

Zn-Fe alloy electroplated steel has excellent corrosion resistance and is used for autobody panels. But the distribution of alloy element in the deposit has marked effect on the corrosion resistance and its precise in-depth analysis is required to determine the construction of the coated layer. Secondary Ion Mass Spectrometry is one of the most useful techniques to accomplish the quantitative in-depth analysis. However the sputter rate of high alloy varies with the concentration of alloy element [1] and it is necessary to anticipate this variation of sputter rate with Fe concentration for Fe-Zn deposit. A new technique based on the calibration curve method [2] was developed to estimate the true quantitative in-depth profile of alloy element in the deposit.