Method and system for predicting surface contact fatigue life

Abstract

A system and method for determining surface contact fatigue life may use a finite element method to determine when components, such as a power transmission component, may fail in operation. The method may generate a finite element model based on the material parameters related to a power transmission component, generate a surface pressure time history for a loading event based on one or more loading parameters, determine, based on the surface pressure time history for a loading event, a finite element solution that describes stress in the grain structure, calculate damage in the finite element solution using a damage model, and determine whether a damage threshold is exceeded.

What is claimed is: 
     
         1 . A method comprising:
 generating a finite element model based on material properties related to a power transmission component, wherein the finite element model describes a grain structure of the power transmission component;   generating a surface pressure time history for a loading event;   determining, based on the surface pressure time history for a loading event, a finite element solution that describes stress in the grain structure;   calculating damage in the finite element solution using a damage model; and   determining whether the damage exceeds a damage threshold.   
     
     
         2 . The method according to  claim 1 , wherein generating a surface pressure time history comprises generating a surface traction time history and a bulk loading time history. 
     
     
         3 . The method according to  claim 1 , wherein generating a surface pressure time history is based on one or more parameters related to the geometry and physical properties of the power transmission component. 
     
     
         4 . The method according to  claim 3 , wherein the one or more loading parameters comprises a surface roughness profile, lubricant properties, and transmitted load. 
     
     
         5 . The method according to  claim 1 , comprising updating the finite element model based on the calculated damage. 
     
     
         6 . The method according to  claim 1 , wherein the material properties related to the power transmission component comprise parameters related to microstructure geometry and physical composition of the power transmission component. 
     
     
         7 . The method according to  claim 1 , wherein generating a finite element model comprises generating a Voronoi tessellation. 
     
     
         8 . The method according to  claim 1 , wherein if the damage threshold is exceeded, a number of load events preceding the damage threshold is output. 
     
     
         9 . The method according to  claim 1 , wherein if the damage threshold is not exceeded, repeating the operations of determining a finite element solution, calculating damage, and determining whether a damage threshold is exceeded. 
     
     
         10 . The method according to  claim 1 , wherein the power transmission component comprises a gear or bearing. 
     
     
         11 . A computer system comprising:
 a memory to store material parameters related to a power transmission component; and   a processor to:
 generate a finite element model based on the material parameters related to a power transmission component, wherein the finite element model describes a grain structure of the power transmission component; 
 generate a surface pressure time history for a loading event based on one or more loading parameters; 
 determine, based on the surface pressure time history for a loading event, a finite element solution that describes stress in the grain structure; 
 calculate damage in the finite element solution using a damage model; and 
 determine whether the damage exceeds a damage threshold. 
   
     
     
         12 . The computer system of  claim 11 , wherein the processor is to update the finite element model based on the calculated damage. 
     
     
         13 . The computer system of  claim 11 , wherein if the damage threshold is exceeded, the processor is to output a number of load events preceding the damage threshold. 
     
     
         14 . The computer system of  claim 11 , wherein if the damage threshold is not exceeded, the processor is to repeat the operations of determining a finite element solution, calculating damage, and determining whether a damage threshold is exceeded. 
     
     
         15 . The computer system of  claim 11 , wherein generating a surface pressure time history is based on one or more parameters related to the geometry and physical properties of the power transmission component. 
     
     
         16 . The computer system of  claim 15 , wherein the one or more loading parameters comprises a surface roughness profile, lubricant properties, and transmitted load. 
     
     
         17 . A method comprising:
 generating a finite element model that models a structure of a machine component;   determining, based on a surface pressure history for a loading event, a finite element solution describing stress in the structure;   calculating a damage level in the finite element solution; and   determining whether the calculated damage exceeds a damage threshold.   
     
     
         18 . The method of  claim 17 , wherein the finite element model is a random microstructure instance. 
     
     
         19 . The method of  claim 17 , wherein the surface pressure history is based on a surface roughness profile, lubricant properties, and transmitted load of the component. 
     
     
         20 . The method of  claim 17 , comprising determining the number of loading events required to exceed the damage threshold.