IMMC Application Showcase

This sampling of the wide variety of parts that are now being injection molded out of metals or ceramics shows process capability as well as end markets for future growth. 

Used as cruise control sensors in luxury automobiles such as Jaguars, these components are constructed of and plated with nickel iron. The parts were designed to take full advantage of MIM capabilities. According to Injectamax Corp. (Escondido, CA), the sensors are complex metal shapes, otherwise impossible to manufacture by any other process. The sensor contains approximately 100 critical dimensions, several with tolerances of ±.001 inch. The sensors have a density of 7.65 to 7.70 g/cu cm.
Photo: Injectamax Corp.

These top and bottom covers, manufactured by Thixotech Inc. (Calgary, AB), are part of a three-component program for Proxima Corp.'s (San Diego, CA) D2 LCD projector. TXM magnesium alloy AZ-91D was used to produce the covers, which have 1.5-mm thick walls. Compared to plastics, magnesium's high stiffness and heat resistance satisfied Proxima's need for a durable product operating in a high-temperature environment. After being molded in a three-slide tool, the net-shape covers are treated in a chromate conversion process and painted.
Photo: Thixotech Inc.

Designed for business travel and presentations, this micro portable projector (top) was molded using TXM by Waffer Industrial Corp. (Taoyuan City, Taiwan). The projector's magnesium casing is stronger than plastic but 30 percent lighter, weighing slightly more than 4 lb. The piece is engineered to keep internal mirrors of the projector aligned, enabling images to be projected properly. Previously, it took close to 2 hours to align the projector's components to achieve a correctly projected image. After switching to TXM, the parts were redesigned into a single complex part (above right) that reduced assembly time to less than 15 minutes.
Photo: Thixomat Inc.

Fiber-optic connectors call for precision crimping that requires increased pull strength. This fully assembled scissor-like crimp tool is designed to assemble a variety of connector styles. Produced by Megamet LLC (St. Louis, MO), the mating halves of the jaws are produced side by side with one side incorporating the gauge numbers. Although the halves are thick and relatively heavy for MIM at approximately 33g each, cost is kept low by using a 2 percent nickel-iron material supplied by BASF Corp. Carbon control during sintering and subsequent heat treatment produces a hardness of 44 to 48 Rockwell C. A black oxide surface treatment provides the necessary corrosion resistance.
Photo: Megamet LLC.

This circular saw gear case was converted from diecasting to TXM by Thixotech (Calgary, AB) for Black & Decker. The diecasting process required heavy machining. The TXM redesign uses an AZ-91D alloy with less than 2 percent porosity. The final result is a net-shape component that requires no machining. Under the previous process, components failed to engage properly, causing numerous warranty issues relating to vibration noise and shortened battery life. Using TXM, Thixotech molds to tolerances three to four times more effectively than diecasting, improving part performance and eliminating warranty concerns.
Photo: Thixotech Inc.

A customer machining the Striker, a component used in commercial aviation as a storage bin latch, reportedly was struggling with slow, expensive production and intolerable material waste. Injectamax Corp. (Escondido, CA) proposed using MIM because the part's size, shape, density, and surface finish requirements made it a good candidate for the process. Because it is a commercial aviation part, production volumes can vary greatly over time, from 5000 to 50,000 annually. By using MIM, production can be scaled back or ramped up quickly without affecting part cost. The component is produced in 17-4 PH stainless steel, has a tensile strength of 20,305 psi, a density of 7.75 to 7.80 g/cu cm, and an as-sintered hardness of 35 Rockwell C.
Photo: Injectamax Corp.