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ABOVE: Bushing cross-section after 70-hour test bed run at 200 ° C( worn surface on the left).
‘ AT 200 ° C FM-T88A DISPLAYS A SIGNIFICANTLY REDUCED DEPTH OF WEAR COMPARED TO A COBALT-FREE MATERIAL AND IS COMPARABLE TO THE RESULTS OF THE HIGH-COBALT MATERIAL, FM-T95A’
P... of the worn specimen showed that the Cobalt-containing
Tenneco sintered materials formed a wear-reducing tribolayer at lower temperatures than the Cobalt-free one. This early forming of a stable tribolayer gave the answer to the first �uestion�
Comparing the samples, the same effect was examined on 17 to 35 per cent Cobalt materials, which provided the answer to �uestion �� �ased on these results, a new material was developed, designated FM-T88A, a sintered steel with 17 per cent Cobalt, which met �roduction and �uality re�uirements, includin� the
manufacturability and mixing of the metal powder, the sintering process, machinability and �uality assurance�
To verify the results of the initial tests, collaborative trials were conducted with a major global vehicle manufacturer comparing the wear resistance of FM-T88A against series production materials. This was undertaken in a test rig which simulated the installation and loading of a turbocharger wastegate bushing running at temperatures of up to 800 ° C.
��he results showed that at �����, ������� dis�lays a si�nificantly reduced depth of wear compared to a Cobalt-free material and is at a
Images © Tenneco Inc.
comparable level of wear resistance to the high-Cobalt material,’ said Wellmann.‘ At all other temperatures the new material’ s performance closely mirrored the high-Cobalt materials.’
‘ With 50 per cent of the Cobalt mined globally now used in batteries for electrified �ehicle �owertrains, demand for the material is growing year on year,’ said Olivetti. ��y minimisin� the le�els of �obalt used in our wear-resistant high temperature sintered materials, we can help our customers mitigate the limited availability and price volatility of cobalt while still delivering robust products.’ Z