NASA'S Role in Aeronautics: A Workshop (1981)

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THE OUTLOOK FOR METALLIC MATERIALS Charles Law McCabe Vice President and General Manager High Technology Materials Division Cabot Corporation Perhaps I should retitle this talk "What Should We Do About Metallic Materials," rather than merely consider their outlook. That's because what we in the U.S. decide to do today and tomorrow will so profoundly affect that outlook. Essentially, then, my remarks will deal with what I think we should do to brighten the outlook for specialty metals, which are the ones I know the most about and the primary ones at issue. Coming from a private sector organization that has a long history in developing specialty metals, I might be expected to sketch either a flattering portrait of our industry's future or a dismal one—depending on the point I might wish to make. But it is because I am a part of an industry whose future depends on the eventual outcome of the issues we're discussing here that I conclude that the outlook for metallic materials depends, to a large extent, on industry and government working together. And as a former college professor, I'll add the academic community to that. To pick up the "outlook" thread, I'll divide it into three parts: —Today, it's not all that bad. —Tomorrow, it's dubious. —The day after, it could be disastrous; or, on the other hand, under control—which it will be is up to us. The current boom in the aerospace industry has seen a period of metallic raw materials allocations and for wrought alloy producers lead times measured in months, even years (rather than weeks). In addition, it has been a period of rapid price increases all the way around. Although the acute shortage phase is over, we are still left with 65

some metallic raw material prices that are artificially high and cannot be sustained over time. I refer particularly to cobalt, which shot up in price during l978 and l979, from $6 to $25 a pound. Unfortunately, most of the free world's cobalt comes from Zaire and Zambia, countries that are desperately in need of cash. Political considerations, rather than marketplace pressures, therefore, dictate selling price. In time, the cobalt price will come down. Generally, though, we shouldn't expect metallic raw materials prices, which have escalated far faster than inflation, to come down. Therefore, pressures that have always existed to find ways of reducing materials costs will be intensified, and good ideas will readily be funded. As for tomorrow, shortages such as we have experienced can be expected to occur again, given the fluctuations in demand by the aerospace industry coupled with a general increase in demand by other markets. The private sector has responded to this situation. Both primary metallic raw materials producers and wrought alloy producers have announced expansion plans. In my own division, our production today in pounds is twice the rate we enjoyed during the peak of the l974 boom period. And just last week we signed a contract that, in l982, will more than double our capacity, as well as improve raw material utilization by increasing yields. With this expansion, we hope that we'll be able to keep our delivery times down in the next boom period so that our customers won't have to order material so far in advance and wait so long for delivery. In most cases, the profit-making system will work in time to provide the necessary productive capacity. But this isn't the whole story and it certainly isn't for the day after tomorrow because there must be an adequate supply of minerals or metallic raw materials to feed the productive capacity and that supply is limited for some important metals. We in the U.S. are particularly vulnerable because l8 of the minerals considered essential to our economy and security are imported at levels of 50 percent or more. Close to l00 percent of two of the most strategic metals for the aerospace industry—cobalt and chromium—are imported. Given that the demand for metallic materials fluctuates and that we import so many of the vital allowing elements, some way of bringing supply and demand into synchronization without worrying about possible cutoffs of foreign sources seems to be the way to go. How best to approach this admittedly idealized situation is the main point I wish to leave with you. Permit me to arrive at this point by summarizing the existing and near-term supply and demand situation and then identifying some basic ideas concerning alternatives to our dependence on foreign existing supplies. The alternatives, each of which I will address, are as follows: —Substitution of those metals whose supplies are most vulnerable to political and other upheavals around the world. 66

—Designing around—that is, eliminating or reducing—the amounts of those metals now being used. —Recycling, or salvaging, those metals during production of components and their eventual disposal. First, I will discuss the outlook for supply and demand over the next five years, focusing on some of our vital and vulnerable strategic metals. Chromium By any criterion, chromium is at the top of the list as a source of concern to anyone who supplies high-temperature alloys to the aerospace industry. The reasons, of course, are that virtually all our chromium is imported and all high-temperature alloys contain about 20 percent chromium for oxidation resistance. The predominant world reserves are in the Union of South Africa and in what was Rhodesia, a region in which there is a great deal of political unrest. Because of its importance and because we don't know what else to do, my company is stockpiling chromium, just in case. Cobalt The high price of cobalt and the experiences of the recent cobalt shortage have spurred mining and extractive metallurgy programs in North America to lessen our dependence on southern Africa. Tantalum The demand for highly efficient, yet miniaturized, circuitry for electronic control devices in applications ranging from defense and automobiles to household smoke detectors and electronic games has placed unprecedented demand on the limited availability of tantalum. Tantalum powder prices have escalated by a factor of five. The best hope now is the discovery of new mineral deposits. Tungsten This is one of the metals that the U.S. possesses and can accommodate about 40 percent of its own demand. Demand is about 20 million pounds, with l0 million pounds being imported (mainly from Canada and Bolivia). During this past boom, tungsten behave! itself—largely because it was avoided in earlier R&D programs because of price and supply, because new productive capacity was installed in response to past shortages, and because the tungsten carbide industry learned to recycle using physical processes that are cheap and quick. Nickel Free world use of nickel is about l.2 billion pounds a year. Most of the 400 million pounds of nickel used in the U.S. is of Canadian origin. Many new mines have been developed in recent years, and currently there is more potential capacity than demand. However, the cost of bringing on new mines has escalated so much that real prices will have to rise for them to be economical. Molybdenum The cost of molybdenum has risen 77 percent (from $9.l0to$l6.20 a pound) since January l, l979. The U.S. is self-sufficient in this critical metallic element. Considerable new production is planned through l987, which should support the forecasted growth rate. Beyond then, new sources will need to be developed, at significant cost, which could very well exceed the capa- bility of any single corporation. 67

Columbium Large columbLum reserves have been identified in Brazil, and production will be expanded to produce about 55 million pounds a year of this metal. So ;nuch for the current situation—now, there are many ways to increase metals supplies: keep world reserves of strategic minerals in friendly hands, increase prices to spur exploration for new sources and exploitation of leaner ore bodies, and do more R&D on extracting metals from lean ore bodies. The big payoff in supply over the long term, however, will be found in other ways. One of these is materials substitution. Substitution in metals can take three avenues: use of other metals or alloys, use of metallic or nonmetallic coatings, and substituting nonmetals for metals. Obviously, substitution is not new, and all these avenues have paid handsome dividends in the past. In the past we have most often substituted to obtain better performance. Now, faced with uncertain mineral supplies, we are looking to substitution to help alleviate the situation or, as we hope, solve the problem. My division has had some recent R&D experiences in substituting nickel for cobalt—experiences that I would like to share with you. Our R&D program to develop a no-cobalt wrought alloy for the combustor can in gas turbines arose because of the $6 to $25 a pound increase for cobalt I mentioned at the start. Even at that price, we were on allocation and facing the sobering alternative of paying $40 a pound on the merchant market. The need for a nickel-base alloy with properties as good as the cobalt alloy was, thus, obvious and highly desirable, so we set to work right away. During the past year and a half we have made remarkable progress in this R&D program because of the large volume of scientific information already in the literature on phase diagrams, metal carbide compositions and morphology, diffusion coefficients of metals in alloys, and the elements of strengthening mechanisms. Without these data, we would not have been able to make nearly as intelligent guesses as to what systems were most promising and we would have been forced to do a great deal of Edisonian-type research. The basic lesson to be learned from this experience is that, in substituting metallic systems in aerospace applications, where the combination of properties required is very specific and very demanding, it is not practical to amass a storehouse of knowledge to deal with every substitution possibility that might be needed. What is needed is more basic scientific data that can be used by researchers to speed up the process of alloy development. Then, as the need arises for a substitute alloy or for a new alloy, it can be developed in a timely fashion. I am not advocating that we, as a nation, do less scientific investigation of the mechanisms of time-dependent processes, such as oxidation, creep, or low-cycle fatigue. Rather, I am saying that we in the U.S. should support more research work aimed at broadly gathering data on systems of potential interest for alloy substitution. 68

This is one of the areas that NASA can boost markedly, chiefly via increased support of research directed toward such data gathering—in universities, government laboratories, and private industry. Certain- ly, this is an area for cost shaving and one for cooperative R&D pro- grams. We now come to design. History tells us that in the aerospace field the outlook, for materials at any given time is intimately tied up with future design. In turn, future design often depends on developments in materials. Today, the need for reduced fuel consumption, reduced weight, increased reliability, and decreased manufacturing costs clearly calls for continued close cooperation between the design and the materials communities. My own experience convinces me that there is room for improvement. I know that in our own allocation of resources to various R&D areas we spend very little of our own funds or time on meeting future needs of design engineers because many of the uncertainties involved. We just do not, in the normal course of business, meet with the key design engineers in industry or government. We would be pleased to spend more of our R&D effort in this area if mechanisms were set up to better define what needs to be dona and if the tasks to accomplish this were split up according to the special expertise of the cooperative private or government organizations. I am sure that other metallic materials producers would be receptive to such a program. Conventional high-temperature metallic materials for gas turbine use have been approaching the limit of development for some time—except now it appears that dispersion-strengthened alloys have a great deal of promise. It is for this reason that there has been increasing emphasis on design to attain the objectives mentioned above. What can materials suppliers do to help? First, materials suppliers can provide product forms and physical characteristics that would be amenable to the new designs and, in some cases, to new manufacturing practices to make the newly designed components. Indeed, we as suppliers of hi^h-performance alloy sheet, bar, plate, wire, and tubing can envision that we could add to that list certain fabricated forms that lend themselves to production in large-scale equipment that we would add to our conventional wrought alloy mill equipment. If required, we can respond to the need for wrought alloys with better welding and fabrication capabilities. As materials are used more efficiently (that is, thinner and in more complex parts), oxidation resistance may become a difficult problem to resolve, requiring responses from different segments of the materials community. Let us now discuss some other avenues we can take to help us adjust to the materials problem. First, alloy design. In designing alloys, the following should be considered (in addition to meeting design targets): —Future availability and cost of raw naterials. —Avoiding the loss of strategic elements in melting returned scrap. —Ability to process in existing large-scale equipment. 69

Second, techniques that allow better utilization—specifically, shaping instead of removing metal—are among the most rewarding actions that can be taken to make the best use of critical materials. Much already has been accomplished in this area, such as producing parts to near net shape using P/M techniques, but a great deal more needs to be done. Still, far too many cutting chips and too much grinding swarf are generated. The pity Ls that many of the alloys in them are not returned to their optimal economic use because they are irretrievably mixed with less expensive alloys. Finally, the above leads to a subject that is of fundamental importance to both the short- and long-term solutions to materials shortages and high costs. It is clear, I'm sure, that the best way to conserve materials is to reuse them. For this to happen, complete cooperation of three groups is mandatory.- —First, the alloy producer. He must segregate his internally generated scrap and develop techniques and proceduras for melting purchased scrap in grade and encourage his customer to return scrap in grade by paying good prices for segregated scrap. —Second, the fabricator of high alloy parts. He should keep grindings and metal chips from diluting a gra.ie, or at least keep cobalt-, nickel-, and iron-base alloys separate. He nust also return these high-grade materials to the original producer, thus preventing them from finding their way into products where some of the strategic elements are not needed to meet specs. —Third, the engine designer. Where possible, assembly should be designed so that different alloys (or families of alloys) can be easily separated when the assembly is finally scrapped, so that the alloys can be sent back to the alloy producer for melting-in grade. The materials outlook for the l980s is such that we simply cannot relax. We have a great many options open to us for short-term solutions to materials availability: we can explore for new deposits, develop known deposits, stockpile in times of recession, and keep the Soviets away from our sources of supply. For a long-term solution to our materials availability problem, however, we must look to substitution, design, and a tight scrap return cycle. These solutions are not new; they have a long and honorable history. But it is not too soon for us to accelerate developments in these areas. 70