10. The Effect of Technological Parameters on the Tensile Strength of Rubber Springs (After Renner, Based on Experimental Design)

This chapter is the most practical part of the book. It presents tests for real manufacturing processes. It is intended to answer the question of what are the physical parameters that, given a quantifiable design, will result in a rubber-metal bond that is both at its maximum and within 5% of the standard deviation of the tensile strength of the rubber-metal transition of the product. To this end, vulcanisation tests are presented, where the metallic surfaces of the metallic arms in contact with the rubber are treated with corundum or steel shot, and after vulcanisation the bond strength is analysed by tensile testing. During the test, profilometric measurements were taken and 3-dimensional roughness values were also investigated. The most important result of the book, the correlation between vulcanisation pressure in the mould cavity and the bond strength developed, can be studied here. A mathematical model was created from the data and verified by statistical methods.