Load carrying capacity and strengthening potential of ausferritic cast iron (ADI) gears

 

Starting Situation

Cast components made of ADI combine tensile strength or elongation at break of steels commonly used in drive technology with the creative freedom of casting technology. In addition, wear-resistant surfaces are formed by martensite transformation under rolling stress, making the material particularly interesting for gear applications. An economic use of this potential-laden material is often prevented by the demanding machinability and lack of knowledge about the strength in gear applications. The strength values determined for material samples are not transferable, especially with regard to rolling strength. There is no systematic work available to determine the strength values according to ISO 6336-5 for a standard bearing capacity verification for the calculation of currently relevant ADI materials.

Research Objective

The aim of the research project is the determination of load carrying capacity values for ausferritic cast iron according to DIN EN 1564 (ADI) for application in the standard concept according to ISO 6336-5 with regard to pitting and tooth root fracture. For this purpose, externally toothed gears are manufactured in two ADI grades and examined and evaluated in pitting and root load carrying capacity tests. Furthermore, the influence of size on a higher-modulus test toothing is investigated. In addition, the service life behaviour in the hobbing and grinding machining of the test specimens is analysed in order to be able to derive production parameters for the machining of ADI in addition to the "ADI Span" project.