Abstract
Spring steel quality has a major impact on spring life. Spring steel quality depends also on the inclusions presence. 7 dynamically tested and broken springs (51CrV4) were analyzed. The dynamic test result is the number of the cycles before spring breakage. We were interested in dependency of the inclusion size and the distance from the surface of the inclusion on the spring tool life. In the paper the genetic programming method was used. In the proposed concept the mathematical models for spring life undergo adaptation. The results show that the proposed concept can be used in practice.