Zhang, X., Han, Y., Huang, E., Pan, A. et al., "Steering Wheel Leather Peeling Off Failure Investigation and Analysis," SAE Technical Paper 2017-01-0320, 2017, doi:10.4271/2017-01-0320.
Customer expectations for improved performance, comfort levels, and aesthetics have led automobile manufacturers to use leather for seats, steering wheels, instrument panels, door panels, and other components. To increase the drivers’ comfort level, there is always a soft pad layer applied under the leather in the steering wheel. This paper will describe a potential failure mode that occurs when materials migrate from one material to another material in multilayer material constructions. In this case dioctyl phthalate migrated from the soft pad layer into the leather surface, affecting the durability performance of the leather coating. This paper describes the failure and demonstrates an effective test methodology to test for this failure during the materials and components validation process.