Patent · US Expired

Method of evaluating high fatigue strength material in high tensile strength steel and creation of high fatigue strength material

US6546808B2 · kind B2 · utility

3Cited by
6References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 31, 2001
Grant dateApr 15, 2003
Priority date
Expiry dateJul 31, 2021

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N33/2045
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

The present invention provides a method of designing a high fatigue strength in high tensile strength steel, comprising: obtaining values of tensile strength &sgr;B (unit thereof is MPa) and Vickers hardness Hv of the steel; measuring a flaw area of an inclusion, when a fracture origin is located only at a surface of the steel; and estimating, in designing the high fatigue strength steel, that a fatigue limit &sgr;w (unit thereof is MPa) of the steel satisfies either &sgr;w≧0.5 &sgr;B or &sgr;w≧1.6 Hv, when a square root of the flaw area, (area)½ (unit thereof is m), contained in the steel is no larger than 45.8/&sgr;B2 or 4.47/Hv2. According to the present invention, a method of evaluating high fatigue strength in high tensile strength steel, in which method a relationship between a flaw dimension (area) of ODA and the fatigue strength is considered, and a high fatigue strength material can be provided.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.