Lee Rogers, Principal Engineer – Electrified Propulsion, at Drive System Design (DSD), outlines how powder metal gears can support EV production and how DSD’s work with industry-leading materials specialist Alvier has supported the development.
Manufacturers throughout the transport industry are aware that they now need to be placing significant investment in cheaper, cleaner, lower carbon technologies to support net-zero goals.
When considering our customers in the European Union (EU) in particular, we know that increasing legislation around lower carbon footprints is placing even more pressure on them to find sustainable electrification solutions.
What are we doing?
In collaboration with Alvier, specialists in advanced materials and production methods for sustainable high-volume applications, we are integrating powder metal gears into an automotive EDU demonstrator. This near-net-shape design eliminates a significant amount of material waste with a minimal difference in package/weight when compared to traditional forged gears.
These gears can be used in a range of vehicle sectors from automotive to off-highway and will enable significant cost savings at high enough volumes. The major reduction in CO2 is also a major bonus as Electric Vehicle (EV) production volumes rapidly increase.
We’re not stopping there. We’re supporting our customers by providing guidance on how to implement the gears into their specific systems, to ensure their needs are met whether they’re manufacturing cars, trucks or tractors.
How did we do it?
Our partnership with Alvier enabled us to replace some traditionally manufactured gears in an EDU with a powder metal counterpart.
Utilising Alvier’s experience in powder metallurgy, which is the process used to develop powder metal gears, we built an understanding of the manufacturing constraints that would apply in volume production. When combined with DSD’s transmission engineering expertise we were able to identify the right component candidates to be replaced with powder metal gears. This led to us identifying the gear wheels as good candidates.
The next step was to understand the differences in material properties. The strength and noise performance of the gears must be equal to or better than a traditional solution to be competitive. DSD performed modal characterisation of both forged and powder metal gears to understand their baseline differences in terms of frequency and damping.
Similarly, using Alvier’s understanding of the powder metal fatigue performance, DSD was able to size the gears to meet the required contact and bending safety factors.
Using the characterised material data we were able to simulate the NVH and strength performance of the gear design against the original requirements. We predicted that these would have similar performance to the existing forged gear wheels. This meant me were able to move onto the prototype stage with confidence that the gears would work successfully.
Before entering the production phase, we used our ePOP tool and costing experience to model the breakeven point of the powder metal gears against the existing forged gears, to understand what volumes would be economically successful.
What’s the result?
The collaborative effort with Alvier throughout the process means we now have the confidence to take this powder metal gear design into prototype hardware. The thorough understanding of the manufacturing constraints, material properties and resulting performance means DSD is primed to help OEMs and Tier suppliers integrate this new technology into their products successfully.
Why DSD?
Successfully integrating new technologies such as powder metal gears to achieve lower cost and carbon footprint requires a collaborative approach that involves both manufacturing and design expertise.