Fatigue crack growth characterization of re-treaded tire rubber

Abstract

Tire re-treading is a re-manufacturing process to tread on tire’s casing. The performance of the re-treaded tire is studied with the qualitative and quantitative research process. From safety point of view, it is very cruical to establish some standard on retreaded tires there are several causes of tire tread failure and no standards are currently in existance therefore the motivation behind this research is to establish a model for fatigue crack growth rate (CGR) prediction for retreaded tire rubber. The progressive simulation model is built to explore the relationship between tearing energy and CGR of the specimen in retreaded tire rubber. An analytical approach is used to check that retreaded tires obey the power-law between tearing energy and fatigue crack growth rate. Testing of the tire rubber specimen from belt edge area is performed for different strains rates. The De Mattia fatigue tester system is used to test the rate of crack growth in a relaxed state in rubber specimens (R = 0).Large volume of data is gathered through testing and regression analysis is done to get the value of the coefficient of determination (R 2 ).This proves that there is a strong correlation between tearing energy and CGR .Results of SPSS simulation also agree with the experimental testing results with less than five percent deviation .CGR in retreaded tire rubber compared with CGR in new tire rubber shows CGRin retreaded titr rubber is significantly higher than that in new tire rubber.Tearing energy decreases moderately however crack grows fast.The findings of this research can be used to improve the quality of the product by small tire retreaders and also useful to policy makers.