Feature article: PIM International, Vol.1 No. 2 June 2007, pages 14-22, 3327 words

Author: Dr David Whittaker, DW Associates, UK

DW Associates, 231 Coalway Road, Wolverhampton, WV3 7NG, United Kingdom

Introduction

The global powder injection moulding industry is making significant progress in finding new applications in the automotive sector. As Dr. David Whittaker reports, Europe leads the way as far as the automotive industry is concerned, but the rest of the world is looking to enter a sector that offers the prospect of relatively stable high volume orders.

Powder injection moulding technology first appeared as long ago as the 1970’s, first in the production of ceramic components (CIM) followed by the development of metal injection moulding (MIM) around the end of that decade. Initially, the automotive industry featured little, if at all, among application sectors. One of the first market penetrations for MIM was in firearm components and this remains an important application sector. Other important application sectors to emerge have been in fashion goods (particularly in watch cases and wristwatch bracelets), sports and leisure goods, household appliances, telecommunication devices, medical/dental devices, cameras and power tools. However, some of these application sectors are very 'fashion conscious' and so specific product designs/applications can be quite short-lived.

On the other hand, although experience suggests that cost is a primary driver in the automotive industry and therefore price levels for components may not be as attractive as elsewhere, once an application has been developed there is security in the knowledge that it is likely to be for the life time of the particular vehicle platform or engine or other sub-system. Also, mainstream automotive applications offer the high production volume requirements needed for a volume-sensitive technology such as PIM to show a cost advantage. So, the automotive sector has become an increasingly interesting marketplace for PIM parts producers.

There are a number of ceramic injection moulded (CIM) parts in automotive usage and these will be identified in this review. However, the bulk of the PIM automotive usage arises from metal injection moulded (MIM) products.

The subsequent sections in this review will seek to:

• quantify the current worldwide sales of PIM automotive products and examine geographical regional variations in automotive usage

• identify key application types

• consider the important materials used in PIM automotive parts, the property levels achievable and the dimensional tolerance control offered by the technology

• highlight some of the leading suppliers of PIM automotive parts

• identify the prospects for and impediments to be overcome to ensure future growth of business in this market sector.....

Further sections of this article include:

- Geographical segmentation of the current impact of PIM automotive applications
- Key Application Types
- Active suppliers of PIM automotive parts
- Materials, properties and tolerances
- Future prospects
- References

Figures and Tables:

Fig. 1 Analysis of MIM activity in Asia by application sector

Fig. 2 Application of MIM activity in Japan by market sector

Fig. 3 MIM component production by world region

Fig. 4 MIM activity in Europe by application sector

Fig. 5 MIM activity in North America by application sector

Fig. 6 Analysis of North American MIM activity by MIMA

Fig. 7 Rocker arm component by Schunk Sintermetalltechnik GmbH, Germany

Fig. 8 Rocker arm components by Nippon Piston Ring Co Ltd, Japan

Fig. 9 Piston cooling nozzle produced by GKN Sinter Metals, Germany (Courtesy EPMA)

Fig. 10 Automotive transmission components by GKN Sinter Metals, Germany (Courtesy EPMA)

Fig. 11 Turbocharger components are now a major application area for MIM (as featured in ‘Injecting more mettle into P/M designs’)

Fig. 12 Turbocharger adjustment ring made by Schunk Sintermetalltechnik GmbH, Germany

Fig. 13 Sensor housing cover made by Schunk Sintermetalltechnik GmbH, Germany

Fig. 14 Burner chamber for independent heating systems for cars and trucks, made by GKN Sinter Metals, Germany

Fig. 15 Sliding block for mechanical steering pillar adjustment. Schunk Sintermetalltechnik GmbH, Germany

Fig. 16 Parts for automotive lock systems. Schunk Sintermetalltechnik GmbH, Germany

Fig. 17 Driving bush for seat backrest adjustment, Schunk Sintermetalltechnik GmbH, Germany

Fig. 18 A typical histogram plot of the data currently held in the database for the tensile strength of 17-4PH stainless steel in the as-sintered condition

Table 1 MPIF Standard 35 for Metal Injection Molded Parts currently covers the above range of low alloy steels, stainless steels and soft magnetic alloy grades

Table 2 Typical mechanical properties for the low alloy steels and stainless steels

Table 3 Typical magnetic properties for soft magnetic grades

Table 4 A European industry guide to what tolerances can typically can be achieved with MIM parts in the as-sintered condition

Table 5 An analysis, provided by Nippon Piston Ring, highlights the reasons for the selection of MIM as the preferred manufacturing technology for their VVT system rocker arm components

Table 6 Minimum and maximum product dimensions as quoted by a MIM producer utilising conventional thermal debinding