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VII.
RECOMMENDATIONS FOR FUTURE
R&D
Methods for reducing friction and wear generally require improvements in one or more of four
areas:
·
Materials.
·
Coatings and surface modifications/conditions.
·
Lubricants.
·
Design methods.
However, it is generally agreed that none of those areas should be treated independently of the
others. For example, performance of a coating will depend on the properties of the substrate and
the mating surfaces (materials), the nature of the lubricant, and the stresses and temperatures to
which it is subjected (design). Different lubricants are needed for different mating surfaces
(materials and coatings) and for different pressures and temperatures (design). Likewise,
material selection depends on design stresses and temperatures, anticipated use of coatings, and
effectiveness of lubricants; and designs are limited by the available or affordable materials,
coatings, and lubricants. Looking at it another way, a given wear problem might be solved by
using a more wear-resistant material or a wear-resistant coating or a better lubricant or a design
that reduces the contact stresses. Therefore, for an optimal solution to a friction or wear
problem, a systems approach should be taken by a team with expertise in each of the critical
areas.
Recognizing the need for advances in all four areas, the workshop participants were divided into
four working groups, each with an emphasis on one of the four areas. Each group was asked to
prepare a list of research topics important to the transportation industry and appropriate for
support from DOE. Despite the fact that each group had a specific technical focus, they were
asked to consider solutions to problems broadly and not ignore the importance of the other three
technical areas.
The following paragraphs summarize the recommendations from each of the working groups.
The recommendations are not listed in order of priority. Priorities were developed later after
considering input from all of the working groups.
A.
Materials
1.
Develop materials or coatings for fuel lines, pistons, and valve trains that are
compatible with alternative ethanol-containing or low-sulfur fuels. The
materials must be suitable for use between 40 and 66
0
C.
Many new fuels are corrosive to currently used materials, and they dissolve
common lubricants, leading to lubricant washout, wear, and scuffing.