- An Overview of the Early PM Timeline
- The Dawn of the PM Industry
- The Start of the MPIF
- Breaking Down the Barriers to Success
- The PM Industry Today
Powder metallurgy (PM) is one of the most interesting and innovative manufacturing technologies to arise since the turn of the 20th century, though its beginnings were as trying as they were auspicious. Despite its relatively recent entrance into the production sector of the modern economy, PM has been around for millennia in some form or other.
Before traversing the murky waters of PM's large-scale advent in the 1900s, let's take a look at its early history, which goes back to at least 3000 B.C., according to "Powder Metallurgy and Particulate Materials Processing" by Randall M. German. At that time, the Egyptians utilized iron powders for fabricating objects, making them one of the first recorded users of PM, along with the Incas.
Thousands of years later, between 35 and 414 A.D., metallurgists in India created the 6.5-ton Delhi column from iron powder. After another period of more than 1000 years, engineers in the 1800s began utilizing metal powders to create laboratory instruments with platinum.
Later in the 19th century, PM played a role in the early days of electricity, when William Coolidge designed a sturdy lamp filament for Thomas Edison that used tungsten powder, German explained. Later, Coolidge created flexible tungsten fibers from powders, providing more illumination and a higher operating temperature than the metallized carbon threads developed by Willis R. Whitney in 1905.
Improvements achieved using PM continued through the early 20th century, with the fabrication of electrical contacts, cemented carbides and porous bearings in the 1930s, and steelmaking refractories and insulators in the following decade.
During its early stages, German said, PM was implemented to expand the spectrum of metals available for various applications - a use that continues to this day. In recent times, the endeavor to increase the range of available materials and resulting characteristics utilizing PM has led to a diverse array of alloys and blends that can be produced by no other method, including tantalum, beryllium oxide, silicon carbide, titanium, rhenium zirconium and titanium diboride. Not only that, but today silica, stainless steel, bronze, copper, aluminum, iron, and alumina come in powdered metal form.
Though PM has been used for many years for a variety of purposes, it didn't really begin to take hold as an industry until the middle of the 20th century, Kempton Roll wrote in the Foreword to "Fundamentals of Powder Metallurgy" by Leander F. Pease, III and William G. West. Around that time, enterprising entrepreneurs started investing in PM, taking major risks in unknown waters that had yet to be explored.
During the Second World War, five major businesses ruled an isolated powder metallurgy parts manufacturing industry. These production powerhouses were the Amplex Division of Chrysler, the Moraine Products Divisions of GMC, Keystone Carbon Co., U.S. Graphite Co. and Boundbrook Oilless Bearing Co. Then, there was only one PM product being manufactured - self-lubricating bearings - for a single market: the automotive.
However, there was sufficient commerce to generate an industry dedicated to the production of metal powders that was populated by little-known spin-off companies of a number of large enterprises that dealt in non-ferrous metals, according to Roll. For instance, New Jersey Zinc Co., National Lead Co., American Metal Climax and Metals Refining Co. were among the smaller businesses that sprung up due to the moderate prevalence of PM at the time. Iron powder makers would come later, as there was practically no viable market for iron powder applications at the time.
Though PM was a fairly secluded industry before and during the war, it began to thrive in the post-war years as more people became interested in the technology. Kempton Roll wrote in the Foreword to "Fundamentals of Powder Metallurgy" by Leander F. Pease, III and William G. West that engineers talked about PM in a mocking manner due to their doubts about its purported potential.
In order to battle these suspicions and other misconceptions with the aim of expanding their market base, powder manufacturers began to work diligently to dispel the doubts of those who could find a use for PM. To this end, a number of companies decided to form their own trade organization in 1944: the Metal Powder Association.
The MPA was active for roughly a decade until maintaining such a membership where any company even remotely connected to the industry had a seat at the table became difficult from a business conflict standpoint in the mid-1950s, Roll explained, and membership declined. However, rather than let the organization continue to falter, members chose to appoint an executive director, leading to the formation of the Metal Powder Industries Federation from the remaining fragments of the MPA. The new executive director and subsequent MPIF staff instead represented the membership for the greater good of advancing the industry relative to standards, education, public relations, programs, and conferences.
The creation of the MPIF proved pivotal for the success of the industry, as it enabled a relatively small group of companies in a novel field to work together to make the case for a new and worthwhile technology. One of the major benefits of the alliance was that it facilitated the spread of information that would lift the veil of ignorance from those who doubted that PM was a legitimate, effective and scientific form of metallurgy. In addition to spreading information about the viability of the powder metallurgy process, the Federation also pushed for greater transparency about the process among and beyond its members, according to Roll.
Many leaders in the MPIF organization supported the motion, but others remained hesitant to divulge their secrets to competitors. Eventually, the whole of the MPIF agreed to share details about the PM process, which ended up having a salutary effect on the industry, contrary to what some feared. Instead of losing business, PM enterprises thrived due to greater acceptance from engineers, who were then better informed about the methods and advantages of sintering with powder metals.
Further, Roll noted that the MPIF provided a unique environment where companies within a single industry could intensely compete, but without compromising the ability to collaborate for a common goal. This flexibility turned out to be a major advantage, as enterprises could join forces to contend reigning technologies, such as machining and die casting, from complete superiority.
In time and in large part thanks to the collaborative efforts of the MPIF and its members, engineers were awakened to the demonstrable benefits of PM, which include the ability to manufacture large amounts of precise, identical and affordable metal components for various purposes and the capacity for creating products from unusual amalgamations of materials. In the Foreword to "Fundamentals of Powder Metallurgy" by Leander F. Pease, III and William G. West, Kempton Roll wrote that at this point customers of the industry began to cease their criticism, instead of becoming more empathetic to those with the wherewithal to pursue this form of manufacturing.
With this new level of consumer understanding, PM companies had less trouble demonstrating to their customers that though a lot of complex work goes into creating quality metal components, the conversion to PM was well worth it. That is, though initial costs might have appeared high to consumers at the time, a deeper grasp of the powder metallurgy process enabled them to see that long-term payoffs could be reaped by choosing and investing in the technology.
In addition to making customers more knowledgeable, the MPIF facilitated a collaboration between enterprises in the industry without fear of being penalized by anti-trust laws, according to Roll. The Federation provided both financial resources and power in numbers that would have been prohibited if the organization's various member companies united into a single business.
In sum, the MPIF helped the PM industry to make the transition from a small isolated industry to a successful and fully global enterprise, blazing the trail to where it is today.
Nowadays, powder metal parts are used in the majority of engineering systems, Randall M. German wrote in Chapter 1 of "Powder Metallurgy and Particulate Materials Processing." He noted that PM was traditionally chosen for its cost-effectiveness, though the number of reasons now leading to its adoption has grown to include productivity, quality, material characteristics and homogeneity advantages.
Moreover, the range of applications that PM is now used for has also expanded from the once narrow market for self-lubricating bearings to fields as disparate as medical technology and computers. For instance, powdered metal manufacturing has provided a solution for heat-dissipation issues with silicon in electronic frameworks by allowing the creation of low thermal expansion and high thermal conductivity heat sinks. In the health care arena, PM has led to the creation of biomedical implants that utilize composite materials with customizable properties.
German explained that today, the primary aspect of the PM industry is parts manufacturing, whether for internal business use or sale to other enterprises. The sector is currently divided mainly by the particular complexity of production process and substances utilized. For instance, only a handful of companies may be able to provide certain sizes of precision parts made with specific materials using die compaction, despite the existence of more than 1500 businesses that utilize the technology in the U.S.
As you might expect then, the PM industry today is very diverse and contains a wide range of enterprises that specialize in one or more of the numerous niche markets within the segment. With such a varied and strong history, PM is sure to continue its success for decades to come.
"Powder Metallurgy and Particulate Materials Processing" - Randall M. German
"Fundamentals of Powder Metallurgy" - Leander F. Pease, III and William G. West