1
Introduction
BACKGROUND
The goal of this study was to determine a materials research agenda for the automotive and commercial aircraft industries during the next two decades. The National Science Foundation (NSF) selected these two industries to be the focus of this report because they exemplify in the broadest sense the challenges, successes, and disappointments of a worldwide economy, where competitiveness through innovation and productivity determines "winners and losers." The contrasts and similarities of these industries are presented in Table 1-1. Collectively, they have an important role in the U.S. (and the world) economy. In the United States, their combined sales of $156 billion in 1991 composed roughly 3 percent of the gross national product, and over one million workers were employed in direct and allied industries.
The importance of these two industries to the country can be clearly seen in the report on the much heralded federal program in materials science and technology, entitled Advanced Materials and Processing Program, recently issued by the Federal Coordinating Council for Science, Engineering, and Technology (FCCSET) of the Office of Science and Technology Policy. The program recommends a supplement to the President's fiscal year 1993 budget to provide a total of $1.8 billion for materials research and development, which is
TABLE 1-1: Comparison of Salient Facts Between U.S. Commercial Aircraft and Automotive Industries for 1991.
FACT |
CIVIL AIRCRAFTa |
AUTOMOTIVEd |
Gross Sales |
$38 billionb |
$118 billion |
Balance of Trade |
$22 billion surplusb |
$36 billion deficit |
No. of Employees |
334,000b |
743,210e |
Units Produced |
589c |
5.4 million |
Value Per Unit |
$46 millionc |
$16,152 |
Estimated Value Per Pound |
$300c |
$5 |
a Source: AIA, 1992 b All civil aviation c Transport aircraft only (excluding helicopters and light aircraft) d Passenger-car fleet only (Source: MVMA, 1992) e Motor vehicle and parts manufacturing only |
a 10 percent increase over the fiscal year 1992 budget. The materials issues for the commercial-transportation sector are stressed in a number of places in the report, for example:
Specifically, materials advances would reduce the weight and increase the operating efficiency of future commercial aircraft. For example, advanced metals and composites, innovative structural concepts, and improved fabrication processes would offer opportunities to make stronger and more cost-effective primary wing and fuselage structures (FCCSET, 1992, 29).
. . . for a new generation of supersonic commercial aircraft. . .advanced ceramic and intermetallic composites would enable the development of affordable engines operating with reduced emissions and at acceptable noise levels, and advanced aluminum alloys and composites would help reduce airframe weight (FCCSET, 1992, 29).
Other advances would help the development of more fuel-efficient cars. . .opportunities lie in the development of processing and fabrication technologies for lightweight composites, high-strength metals, and tough ceramics, that will enable mass production and recycling at acceptable costs. . .(FCCSET, 1992, 30).
NSF also hopes that the materials issues for the commercial aircraft and automotive industries could have applications to other industrial and transportation sectors dependent upon advanced structural materials, such as the construction, rail, and marine vessel industries.
CASE STUDIES FOR THE REPORT
Since many of the materials issues are best illustrated by considering specific examples, and to focus the study further, a case study from each of the industries was selected for discussion within the report. The committee selected two from a number of exemplary systems that were proposed by the respective committee experts at their first meeting: the high-speed civil transport (HSCT) for the aircraft industry and the energy-efficient vehicle for the automobile industry (i.e., the 50-mpg, 5-passenger sedan). These two examples were chosen because both are seen to be potential commercial industry priorities during the next 10–20 years and could benefit from extensive materials innovations.
The HSCT, which is expected by the National Aeronautics and Space Administration (NASA) and Boeing to be introduced into service in approximately 15 years, responds to a growing market for long-range, international commercial aircraft. System studies have suggested that a high-speed transport with the properties shown in Table 1-2 may be economically viable. Key technologies have advanced since the introduction of the Concorde over 20 years ago, and further research is currently being funded by NASA. Market studies have suggested that by the year 2015, 32 percent of international travelers, some 600,000 passengers per day, might utilize a service that could be provided by an HSCT (Boeing Commercial Airplanes, 1989; Douglas Aircraft Company, 1990; Peterson and Holmes, 1991). As stated above in one of the quotes from the FCCSET report, materials advances are integral to the development of this new generation of supersonic commercial aircraft.
The HSCT was selected as the aircraft case study for two reasons. First, the severe service environment of the HSCT provides a "worst case" target for materials development. The materials requirements for the HSCT are far more rigorous than for subsonic aircraft. Materials and structures innovations developed for the HSCT would be applicable to subsonic aircraft, whereas the converse would not
TABLE 1-2: HSCT Market Requirements (Source: Boeing Commercial Airplane Group).
Market Coverage: |
250 to 300 passengers 5,000 nmi initial range with growth to 6,500 nmi Efficient operation on Atlantic/Pacific routes |
High Use: |
Conventional airport operation 1-hr turn time Highest economical Mach number |
Passenger Acceptance: |
Significant time savings Comfort equivalent to subsonic Accelerations similar to existing subsonic Seat cost no more than 10–15% above subsonic |
Environmental Acceptability: |
Not significantly impact stratospheric ozone Quiet airport operation similar to Stage III subsonic Not produce perceptible boom over populated areas |
necessarily be true. Second, the more extreme operational requirements of the HSCT aircraft also means that a broader spectrum of technologies (e.g., polymeric composites, advanced metallics, ceramic and metallic matrix composites, sealants, adhesives, and finishes) must be investigated than for subsonic aircraft. Thus, as a case study for materials, the HSCT provides a wide range for discussion.
The 5-passenger sedan is a mainstay of the U.S. automotive industry. Even 15 years after the energy crisis of the 1970s, midsize and large sedans still account for almost 40 percent of the U.S. sales market, the same combined market share as in 1975 (EEB, 1992). However, Corporate Average Fuel Economy (CAFE) standards are
expected to increase in the future. The current, most successful method for improving fuel efficiency is to reduce the weight of automobiles (OTM, 1993). If 5-passenger automobiles are to continue to meet CAFE standards, methods must be developed for increasing fuel efficiency without sacrificing passenger space.