ABSTRACT
This study is aligned with the objective of the research project to support small business in the development of regional components. It is presented an analysis case performed as assistance to a producer in search of optimization in the quality of his line of agricultural use. The study applicant needs to find a root cause of the difference in in-service behavior of the lateral rake teeth between those of their own manufacture and others available on the local market. These are curved steel rods with a diameter of 8 mm x 1300 mm, which are integrated into multi-tooth wheels which must show a totally elastic behavior during their use.
The study is carried out on 4 samples received from different manufacturers.
Using chemical and metallographic analysis, microhardness measurement and tensile tests, the characteristics of the different samples have been compared.
It is concluded that the heat treatment of quenching and tempering, subsequent to the cold forming of the rod, increases the limit of elasticity by an average of 45% relative to the pieces that only have cold plastic deformation. [33 FAILURE ANALYSIS AND PREVENTION – Metals Handbook. ASM. – v. 11. 9a ed. pp. 136 -144., 44 “Endurecimiento del acero”, REED HILL R.E. Principios de Metalúrgica Física -2aed.cap.17, CECSA, 1971., 55 HTUN M.S., KYAW S.T., LUIN K.T., Effect of Heat Treatment on Microstructures and Mechanical Properties of Spring Steel, Journal of Metals, Materials and Minerals, v. 18, n. 2, pp.191-197, 2008., 66 SMITH W., HASHEMI J., Fundamentos de la Ciencia e Ingeniería de Materiales, McGraw-Hill, Cuarta Edición, pp 271-305, 2008., 77 ASTM - A 370 – 05 - Standard Test Methods and Definitions for Mechanical Testing of Steel Products.]
Keywords
tooth; rake; elasticity; cold forming
