The Objective
A long-standing prime defense contractor approached Allegheny Performance Plastics to evaluate if a small wiring strain relief component, for a missile system, could be converted from metal to plastic.
While metal was the default material for this defense application, the customer’s engineering team recognized an opportunity to reduce both weight and manufacturing costs. The component also required electrical conductivity.
The Challenge
A metal to polymer conversion presented several challenges. The existing metal design has to be altered to accommodate the injection molding process, and the replacement material needed to maintain both electrical conductivity and mechanical strength. For many legacy defense programs, the cost and complexity of material requalification makes metal the default choice, even when high-performance polymers may offer significant advantages.
The Solution
This project utilized every step of our proven five-step process. From the initial review of the existing component, our engineering team recommended a conductive polymer, a carbon-filled PPS, and performed several Design for Manufacturability (DFM) processes, including flow simulation. To create prototypes, we molded our own stock shapes, and machined the parts from our proprietary stock shapes. After the customer tested our protoypes to validate, we manufactured a tool and qualified it for production.
“Many defense applications are low-volume compared to other industries, so engineers may not believe there is a justification for conversion to plastic,” said Andy Lesser, Allegheny’s VP of Sales. “This is a great example of a part that, even at low volume, generated significant cost savings, in addition to a reduction in weight without sacrificing performance or conductivity.”
In addition to the five-step process and engineering support, Allegheny also provided several hours of training to the customer’s Engineering staff. The course, Polymers 101, provided support to help them better understand where high-performance thermoplastics can replace metal in future applications.
