Method of steel grade determination for steel material

Patent metadata

Field	Value
Publication number	US-9291584-B2
Application number	US-201213981965-A
Country	US
Kind code	B2
Filing date	Jan 19, 2012
Priority date	Jan 31, 2011
Publication date	Mar 22, 2016
Grant date	Mar 22, 2016

Abstract

The method of steel grade determination for a steel material having a substantially circular cross-section comprise: a detection step in which while a measurement section 2 including an irradiation section 21 for performing X-ray irradiation and a detection section 22 for detecting fluorescent X-rays is relatively moved along an outer peripheral surface of the steel material 4 with respect to the steel material for a predetermined time period necessary for analysis, the steel material is irradiated with X-rays from the irradiation section, and fluorescent X-rays radiated from the steel material are detected by the detection section; a calculation step of calculating a composition of the steel material based on fluorescent X-rays detected in the detection step; and a determination step of determining a steel grade of the steel material according to the composition calculated in the calculation step.

First claim

The invention claimed is:

1. A method of steel grade determination for a steel material having a substantially circular cross-section and a surface layer oxide scale on an outer peripheral surface thereof, by means of a fluorescent X-ray analysis method in a manufacturing line of the steel material, the method of steel grade determination for a steel material having the substantially circular cross-section comprising:
a detection step in which while a measurement section including an irradiation section for performing X-ray irradiation and a detection section for detecting fluorescent X-rays is relatively moved along an outer peripheral surface of the steel material with respect to the steel material for a predetermined time period necessary for analysis, the steel material is irradiated with X-rays from the irradiation section, and fluorescent X-rays radiated from the steel material are continuously detected by the detection section while the measurement section is relatively moved;
a calculation step of calculating an averaged composition of all of portions of the steel material in which fluorescent X-rays are detected, based on an energy spectrum obtained from a number of fluorescent X-ray counts at each energy level of the fluorescent X-rays detected while the measurement section is relatively moved in the detection step; and
a determination step of determining a steel grade of the steel material according to the composition calculated in the calculation step.

2. The method of steel grade determination for a steel material having a substantially circular cross-section according to claim 1 , wherein
the steel material contains not less than 9 mass % of Cr and contains Ni, and in the determination step, a steel grade of the steel material is determined according to the composition and according to a ratio between Cr and Ni concentrations in the composition.

3. The method of steel grade determination for a steel material having a substantially circular cross-section according to claim 1 , wherein
a distance of the relative movement of the measurement section along an outer peripheral surface of the steel material with respect to the steel material is not less than ½ round around the steel material and not more than 2 rounds around the steel material.

Assignees

• Fujiwara Kenji
• Kubota Hiroshi
• Nippon Steel & Sumitomo Metal Corp

Inventors

• Fujiwara Kenji
• Kubota Hiroshi

Classifications

• G01N23/223 Primary

  by irradiating the sample with X-rays or gamma-rays and by measuring X-ray fluorescence · CPC title

• G01N2223/076

  X-ray fluorescence · CPC title