US 2018/0004873 A1Published application

Surface shape defect generating region estimating method, surface shape defect source region estimating method, surface shape defect generating region estimating device, surface shape defect source region estimating device, program, and recording medium

AssigneeNippon Steel & Sumitomo Metal Corporation

InventorsTakuya KUWAYAMA, Takashi ARIGA

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Abstract

There is provided a surface shape defect generating region estimating method for estimating a generating region of a surface shape defect of a deformation-processed product obtained by performing deformation processing with respect to a workpiece, the method including: a first stress distribution obtaining process of obtaining first stress distribution σT1; a second stress distribution obtaining process of obtaining a second stress distribution σ(T2); a comparative stress distribution obtaining process of obtaining comparative stress distribution σ(T1, T2); a division comparative stress distribution obtaining process of obtaining division comparative stress distribution σ(T1, T2); and a surface shape defect generating region estimating process of estimating whether or not each of the divided regions DK is a generating region of the surface shape defect.

Claims34

Dependent claims

A surface shape defect generating region estimating method for estimating generating regions of a surface shape defect of a deformation-processed product obtained by performing deformation processing with respect to a workpiece from a deformation processing starting point of time TSTART to a deformation processing ending point of time TEND, the method comprising:

a first stress distribution obtaining process of obtaining first stress distribution σ(T1) which is distribution of a stress of the workpiece at a first working point of time T1 that is after the deformation processing starting point of time TSTART and before the deformation processing ending point of time TEND, by a finite element method;
a second stress distribution obtaining process of obtaining a second stress distribution σ(T2) which is distribution of a stress of the workpiece at a second working point of time T2 that is after the first working point of time T1 and before or at the same time as the deformation processing ending point of time TEND, by the finite element method;
a comparative stress distribution obtaining process of obtaining comparative stress distribution σ(T1, T2) which is distribution of a comparative stress of the workpiece based on comparison of the first stress distribution σ(T1) and the second stress distribution σ(T2);
a division comparative stress distribution obtaining process of obtaining division comparative stress distribution σDIV(T1, T2) which is distribution of comparative stresses of each of divided regions DK, by dividing the comparative stress distribution σ(T1, T2) into a plurality of divided regions DK;
and
a surface shape defect generating region estimating process of estimating whether or not each of the divided regions DK is a generating region of the surface shape defect, based on a surface shape defect generation evaluation index a acquired with respect to each of the divided regions DK, by using the division comparative stress distribution σDIV(T1, T2).

3 more elements

A surface shape defect generating region estimating device which estimates a generating region of a surface shape defect of a deformation-processed product obtained by performing deformation processing with respect to a workpiece from a deformation processing starting point of time TSTART to a deformation processing ending point of time TEND, the device comprising:

a first stress distribution obtaining portion which obtains first stress distribution σ(T1) which is distribution of a stress of the workpiece at a first working point of time T1 that is after the deformation processing starting point of time TSTART and before the deformation processing ending point of time TEND, by a finite element method;
a second stress distribution obtaining portion which obtains second stress distribution σ(T2) which is distribution of a stress of the workpiece at a second working point of time T2 that is after the first working point of time T1 and before or at the same time as the deformation processing ending point of time TEND, by the finite element method;
a comparative stress distribution obtaining portion which obtains comparative stress distribution σ(T1, T2) which is distribution of a comparative stress of the workpiece based on comparison of the first stress distribution σ(T1) and the second stress distribution σ(T2);
a division comparative stress distribution obtaining portion which obtains division comparative stress distribution σDIV(T1, T2) which is distribution of the comparative stress of each of divided regions DK, by dividing the comparative stress distribution σ(T1, T2) into a plurality of divided regions DK;
and
a surface shape defect generating region estimating portion which estimates whether or not each of the divided regions DK is a generating region of the surface shape defect, based on a surface shape defect generation evaluation index a acquired with respect to each of the divided regions DK, by using the division comparative stress distribution σDIV(T1, T2).

3 more elements

Dependencies are inferred from the claim text.