Winners of the EPMA’s 2007 Excellence in Powder Metallurgy Awards. The winning entries highlighted the capabilities of powder metallurgy and demonstrated the continuing advancements in the PM industry.
Metal Injection Moulding
MIMItalia of Vado Ligure, Savona, Italy, received an Award of Merit for its patented double bulge diamond bead (Fig. 1) produced by MIM. The fabrication of the beads for diamond wires for stone cutting is commonly performed by means of hot pressing, both uniaxially and isostatically, but more and more often by means of the press-and-sinter route. In the former processes the densification of the powders is aided by a pressure applied by a graphite ram or by a inert gas; however, in the press-and-sinter process densification occurs at low pressure (or vacuum) only because of the effect of temperature.
In all cases a preforming of the green bead by means of uniaxial cold pressing is required. A totally new system diamond bead with a double bulge profile using patented MIM technology has been developed and a trade mark has been deposited. The MIM diamond beads have been fabricated and tried on a full scale test.
Highly Commended in this category was a MIM automatic tuner for electric guitars (Fig. 2) produced by Maxon Motor of Sexau, Germany. Fulfilling the very challenging requirements of the customer this device helps guitarists to keep their guitar perfectly tuned and reduces the retuning time of a guitar to 1.5 seconds. An experienced technician would take 30 seconds. The guitar tuner shows the possibility of MIM to produce small, precision and complex parts.
A further component highly commended by the EPMA in this category was for a gear set made by MG Minigears of Padova, Italy, comprising two components, the gear and pinion (Fig. 3) used in a bush cutter. The pinion gear was particularly challenging as the tooth density is crucial to fulfil the customer requirements. The customer undertakes gearhead assembly tests for strength and endurance, the two gears are the most critical components.
Ferrous Structural PM Components
Federal Mogul Sintertech SAS of Veurey-Voroize, France received an Award of Merit for a high density ferrous transfer case sliding sleeve (Fig. 4) which is produced by high pressure compaction. This part is used in a transfer case on 4WD SUV’s. It combines two main functions: the upper part is a sliding sleeve similar to what could be found in a standard manual transmission and the lower part a ring gear as in an automatic transmission planetary assembly. This part was originally made out of two wrought steel forged parts (sliding sleeve and ring gear), with the sleeve press fitted on the ring gear then welded onto it.
A ferrous P/M sliding sleeve (Fig. 5) produced by PMG Füssen GmbH, Füssen, Germany, was Highly Commended in this category. The PM sleeve is designed for a synchronising unit for a 5 speed manual transmission gearbox used in a light truck with a torque up to 300 Nm. Capability for all requested dimensions is guaranteed by the material and process.
Hoeganaes Corp. of Cinnaminson, NJ, USA, received an Award of Merit in this category for AncorMax 200, introduced in Jan 2006. This is a specially formulated lubricant-binder system that allows density of 7.5g/cm3 to 7.58g/cm3 to be achieved in ferrous PM parts processed at conventional sintering temperature with minimal capital investment. This product is applicable to all ferrous material systems and is said to open up opportunities for PM in the billion dollar market for automotive gearing, sprockets, parking brakes etc.
A metal injection moulded (MIM) copper cold plate (Fig. 6) produced by Acelent Technologies, Singapore, was Highly Commended in this category. This MIM part takes full advantage of the benefits of the MIM process, and provides shape complexity capability that gives the designer the maximum flexibility in design concept such as the intricate oval shaped pin geometry of high aspect ratio to provide the optimal thermal performance. The sheer number of small pins, at 279, to be packed within a small confined space, maximises the overall surface area and hence optimises the thermal efficiency. In this regard, it gives the thermal performance of the MIM cold plate an added competitive edge compared with other manufacturing processes.
Uddeholm Tooling AB of Hagfors, Sweden, was given an Award of Merit for the development of the new PM tool steel (Vancron 40) (Fig. 7) using advanced thermodynamic computer calculation (Thermo Calc) methodology. It was envisaged, based on previous experiences, that a martensitic tool steel with a high amount of dispersed, hard carbonitrides, primarily vanadium carbonitrides should have the demanded material and functional properties. It was then possible to calculate the steel composition, which in turn gave the required amount and composition of the different phases and of the martensitic matrix.
The EPMA awards were presented at the EuroPM2007 Congress held in Toulouse, France, October 15-17.