Table of Contents
Forming of Lightweight Materials for Automotive Applications
Contact Information: Richard J. Fields
Automobile manufacturing is a materials intensive industry
that involves about 10% of the US workforce. In spite of the use
of the most advanced, cost effective technologies, this
globally competitive industry still has productivity issues related
to measurement science and data. Chief among these is
the difficulty encountered in die manufacture for sheet
metal forming. In a recent ATP sponsored workshop (The
Road Ahead, June 20-22, 2000, at U. S. Council for
Automotive Research (USCAR) Headquarters), the main obstacle to
reducing the time between accepting a new design and actual
production of parts was identified as producing working die sets.
This problem exists even for traditional alloys with which
the industry is familiar. Figure 1 shows an example of where the
cost of tooling (dies) is the largest single cost in the production
of parts for small cars. (This does not include assembly costs.)
Figure 1. Part cost breakdown for small cars.
(Kelkar et al., J. of Metals, pp 28-32, Aug 2001.)
To benefit from the weight saving advantages of high
strength steel and aluminum alloys, a whole new level of
formability measurement methods and data is needed, together with a
better understanding of the physics behind metal deformation.
This project is meeting the industrial needs (see Table 2) by
developing standard formability test methods, multiscale,
physically-based constitutive laws, and models for consolidation
of aluminum matrix composites. In the past year, we
have established a sheet metal formability laboratory. A
state-of-the-art formability testing machine equipped with an
advanced surface displacement analysis system permits us to
investigate industrially important measurement problems in formability
and pursue standard test methods for formability. The
facility provides test samples of biaxially deformed metal for
other aspects of this program. For example,
deformation-induced surface roughening of sheet metal is a poorly
understood phenomenon that is highly relevant to industry. We are
currently performing controlled experiments on biaxially strained sheets
to develop a surface roughening data base and a generic
model which industry has identified as a high priority need.
Table 1. Industries needs being met by NIST solutions.
On a more fundamental level, we are using MSEL's
advanced characterization capabilities such as transmission
electron microscopy, synchrotron radiation, and neutron scattering at
the NIST National Center for Neutron Research to understand
the basic dislocation patterning responsible for the
observed behavior of metals. A predictive model based on
percolation theory has been developed from the measurements and
observations. All aspects of the research at NIST will impact
our customers by improving the commercially available,
finite element computer codes that are heavily used by this
industry. A key element in the design of this program is that an insight
or advancement gained in one area can be immediately used in
a piecewise fashion in the design process, i.e., total success of
the program is not required to have an impact. Other means
of transferring this technology, such as through
standardizing organizations and by direct interaction with industrial
counterparts, are being pursued. While targeting the auto industry,
our research will have extended applications to all other
industries that employ metal forming in their production lines.
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Materials for Magnetic Data Storage
Contact Information: Robert D. Shull
For the magnetic data storage industry, the market potential
is vast and growing, but global competition is intense, and
the technical challenges extreme. Leading commercial magnetic
disk drives today store about 25 gigabits of data per square inch.
The National Storage Industry Consortium (NSIC) plans to
demonstrate a recording density of 1 terabit per square inch40
times today's levelby 2006.
New materials are needed that have smaller grain structures,
can be produced as thin films, and can be deposited uniformly
and economically. Recording heads must be designed to
produce higher output signals and lower noise. Component
dimensions must be made smaller, and the measurements more precise.
New lubricants are needed to prevent wear as spacing between
the disk and head becomes smaller than the mean free path of
air molecules. New methods are needed to standardize
components and increase yields.
The National Institute of Standards and Technology is
working to achieve these goals. For the past century, NIST has
been helping U.S. magnetic data storage industries invent
and manufacture product with superior reliability. NIST offers
state-of-the-art technology, measurement tools, and
standardsmany of which cannot be found elsewhereas well as a reputation
for technical excellence and neutrality. Staff expertise spans all
fields relevant to magnetic data storage, including materials
science, electrical engineering, physics, mathematics and
modeling, manufacturing engineering, chemistry, metrology, and
computer science. By addressing important measurement issues
in magnetism, by bringing together the industrial and
scientific communities through the organization of workshops
and conferences in the area, and by the development and
preparation of appropriate standards, NIST acts to accelerate the use
of advanced magnetic data storage materials by the industrial
sector, and to enable industry to take advantage of new discoveries
and innovations. In addition, close linkage with NSIC increases
the industrial relevance of our program and improves
technology transfer. Additional collaborations with Xerox, General
Motors, Hewlett Packard, IBM, Seagate, and Motorola Corporations,
for example, enable NIST to leverage its activities with the
much larger, but complementary, capabilities of other organizations.
In FY2001, the Program on Materials for Magnetic Data
Storage in the Materials Science and Engineering Laboratory focused
on the following projects that were continued from the
previous year:
Processing of magnetic multilayers for optimal giant
magnetoresistance effect (Metallurgy Division)
Magnetic domain imaging and micromagnetic modeling
of magnetic domains for understanding magnetization
statics and dynamics in recording heads and magnetic
media (Metallurgy Division)
Understanding the nanotribology of magnetic hard
disks through the measurement of stiction, friction, and wear
at the nanometer scale (Ceramics Division)
Measuring nanoscale magnetic interactions and structure
in multilayers, nanocomposites, and low
dimensional systems, needed for understanding and applying
materials physics at small scales (Metallurgy Division,
NIST Center for Neutron Research)
Measuring and understanding the origin of magnetic
exchange bias in conventional and advanced magnetic structures
and devices (Metallurgy Division, NIST Center for
Neutron Research)
Developing a measurement system for magnetic
susceptibility of small samples at high frequencies
(Metallurgy Division)
Preparing magnetic measurement standard reference
materials. (Metallurgy Division)
Two new projects were initiated in FY2001:
Processing and measuring the properties of
"spintronic" systems wherein spin-dependent magnetic devices
are integrated directly onto semiconductor chips
(DARPA-sponsored; Metallurgy Division)
Developing measurements of magnetic damping
(NIST Nanotechnology Initiative Funding with EEEL;
Metallurgy and Materials Reliability Divisions.)
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Materials for Microelectronics
Contact Information: Frank W. Gayle
Today's U.S. microelectronics and supporting
infrastructure industries are in fierce international competition to design
and produce new smaller, lighter, faster, more functional, and
more reliable electronics products more quickly and economically
than ever before.
Recognizing this trend, in 1994 the NIST Materials Science
and Engineering Laboratory (MSEL) began working very
closely with the U.S. semiconductor, component and packaging,
and assembly industries. These early efforts led to the
development of an interdivisional MSEL program committed to
addressing industry's most pressing materials measurement and
standards issues central to the development and utilization of
advanced materials and material processes within new product
technologies, as outlined within leading industry roadmaps. The
vision that accompanies this program - to be the key resource
within the Federal Government for materials metrology
development for commercial microelectronics manufacturing - may be
realized through the following objectives:
Develop and deliver standard measurements and data;
Develop and apply in situ measurements on materials
and material assemblies having micrometer- and submicrometer-scale dimensions;
Quantify and document the divergence of material
properties from their bulk values as dimensions are reduced
and interfaces contribute strongly to properties;
Develop models of small, complex structures to substitute
for or provide guidance for experimental
measurement techniques; and
Develop fundamental understanding of materials needed
in future microelectronics.
With these objectives in mind, the program presently consists
of twenty separate projects that examine and inform industry
on key materials-related issues, such as: electrical,
thermal, microstructural, and mechanical characteristics of
polymer, ceramic, and metal thin films; solders, solderability and
solder joint design; photoresists, interfaces, adhesion and
structural behavior; electrodeposition, electromigration and stress
voiding; and the characterization of next generation interlevel and
gate dielectrics. These projects are conducted in concert
with partners from industrial consortia, individual
companies, academia, and other government agencies. The program
is strongly coupled with other microelectronics programs
within government and industry, including the National
Semiconductor Metrology Program (NSMP) at NIST.
FY2001 Projects (and division leading project)
Lithography/Front End Processing
Characterization of Ultrathin Dielectric Films (Ceramics)
Lithographic Polymers (Polymers)
On-chip Interconnects
Interconnect Materials and Reliability Metrology (Materials Reliability)
Measurements and Modeling of Electrodeposited Interconnects (Metallurgy)
Thin Film Metrology for Low K Dielectrics (Polymers)
Packaging and Assembly
Packaging Reliability (Materials Reliability)
Solder Interconnect Design (Metallurgy)
Solders and Solderability Measurements for Microelectronics (Metallurgy)
Tin Whisker Mechanisms (Metallurgy)
Wafer Level Underfill Experiment and Modeling (Metallurgy)
Wire Bonding to Cu/Low-K Semiconductor Devices (Metallurgy)
X-ray Studies of Electronic Materials (Materials Reliability)
Crosscutting Measurements
Dielectric Constant and Loss in Thin Films and Composites (Polymers)
Electron Beam Moiré (Materials Reliability)
Ferroelectric Domain Stability Measurements (Ceramics)
Measurement of In-Plane Thermal Expansion and Modulus of Polymer Thin Films (Polymers)
Mechanical Properties of Thin Films (Ceramics)
Permittivity of Polymer Films in the Microwave Range (Polymers)
Polymer Thin Films and Interfaces (Polymers)
Texture Measurements in Thin Film Electronic Materials (Ceramics)
Thermal Conductivity of Microelectronic Structures (Materials Reliability)
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Metals Characterization
Contact Information: Samuel R. Low, III
Engineering design depends on the specification of the
properties of the materials that are used. Equally important,
manufacturers and their suppliers need to agree on how these properties
should be measured. The MSEL Metals Characterization
Program, centered within the Metallurgy and the Materials
Reliability Divisions, spans the measurement spectrum from the
innovative use of state-of-the-art measurement systems, to leadership in
the development of standardized test procedures and
traceability protocols, to the development and certification of
Standard Reference Materials (SRMs).
The NIST effort in metals characterization has a strong
emphasis on electron microscopy, which is capable of revealing
microstructures within modern nanoscale materials and
atomic-resolution imaging and compositional mapping of complex crystal
phases with novel electronic properties. The MSEL microscopy
facility consists of two high-resolution transmission electron
microscopes (TEM) and a high-resolution field-emission
scanning electron microscope (FE-SEM) capable of resolving
features down to 1.5 nm. Novel experimental techniques using
these instruments have been developed to study the
mechanical properties of multilayered and nano-scaled materials.
The Metals Characterization Program is contributing to
the development of test method standards through
committee leadership roles in standards development organizations such
as ASTM and ISO. In many cases, industry also depends
on measurements that can be traced to NIST Standard
Reference Materials (SRMs). This program generates the following
SRMs for several quite different types of measurements.
Hardness of Metallic Materials (Metallurgy Division):
Hardness is the primary test measurement used to determine and
specify the mechanical properties of metal products. The
hardness standardization project is providing industry with
primary transfer standards for the Rockwell hardness and Vickers
and Knoop microhardness scales. These SRM test block
standards are used for the periodic calibration of hardness testing machines.
Magnetic Properties (Metallurgy Division): The need for
reliable magnetic measurements is becoming increasingly acute
because of new technologies involving magnetic phenomena in
data storage and microelectronics. Such measurements
require calibration of magnetometers using certified magnetic
standards in several different shapes and magnetic strengths, and with
a wide range in magnetic character. These standards are now
being produced under this program.
Coating Thickness (Metallurgy Division): Coating
thickness standards are produced by electrodeposition and are widely
used for calibration of coating-thickness measuring instruments.
SRM coupons are produced with a wide range of thicknesses, and
are bar coded to allow analysis of degradation and life
expectancy when the standards are returned for verification.
Charpy Impact (Materials Reliability Division): The
Charpy impact machine verification project provides rapid,
accurate assessment of test data generated by our customers using
SRM Charpy standards, and, where merited, certifies the
conformance of Charpy impact test machines to ASTM Standard E
23. Participation in ISO Committee TC 164, assures that
specimens and procedures are compatible with international standards.
In addition to the SRM activities above, NIST
(Materials Reliability Division) provides assistance to the Bureau
of Reclamation (BOR) on metallurgical issues that arise
during maintenance, inspection, and failure assessment of dams
and water conveyance infrastructure projects. NIST advice and
data provide BOR engineers with an independent check of
other input.
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Metals Processing
Contact Information: Stephen D. Ridder
The Metals Processing Program applies NIST expertise in a
wide range of disciplines, including thermodynamics,
electrochemistry, fluid mechanics, diffusion, x-ray, and thermal analysis,
to understand the processing steps which will lead to
products having the desired form and properties, at an acceptable
cost. Working with industries ranging as widely as
automotive, aerospace, coating, and microelectronics, several
important processing problems are being addressed including melting
and solidification of welds, castings of single crystals,
powder production and consolidation, and coating production by
thermal spray and electrodeposition.
The increasingly competitive manufacturing environment
fuels the search for new metal alloys as well as efficient
processing techniques to fully realize their potential. The processing
cycle can include many steps, including a formation process such
as casting or electrodeposition, a heat treatment process, a
deformation process such as rolling or stamping, joining by welding,
or coating to enhance surface properties. In each of these
processes, the distribution of crystal phases, the grain structure, the
alloy compositional segregation, and the defect structure are
altered, with resulting changes in properties such as strength,
ductility, corrosion resistance, and conductivity which form the
basic rationale for the use of metals in industrial products.
The following projects in the Metals Processing Program focus
on measurements and predictive models needed by industry
to design improved processing methods, provide better
process control, develop improved alloy and coating properties,
and reduce costs.
Modeling of Solidification and Microstructure
Development: (Metallurgy Division): Models of alloy
solidification, crystal growth processes and heat treatment are
being developed to aid industry in designing production
systems that increase product yield and performance.
Processing-Structure-Property Data For Thermal
Spray Coatings (Metallurgy Division): Coating
reproducibility and reliability are addressed by the development
and calibration of advanced sensors, applying these
measurement tools to the control and characterization of
TS coatings, and working with the Thermal Spray
(TS) community to establish a coating
processing-microstructure-property database.
Weld Process Sensing, Modeling and Control
(Materials Reliability Division): Advanced instrumentation and
data analysis techniques are used to develop a better
understanding of the underlying physics governing the
arc welding process.
High-energy X-ray Diffraction Studies (Materials
Reliability Division): Investigations are underway on the use of
high-energy x-ray diffraction as an alternate,
nondestructive option to the conventional destructive methods
for measuring physical properties.
Tailored Metallic Powders (Metallurgy Division):
Measurement techniques for the characterization of microengineered powders are developed to advance
our understanding of the relationships among
properties, processing, and microstructure.
Electrodeposition of Aluminum Alloys (Metallurgy
Division): Guidelines for the electrodeposition of
aluminum-based alloys from low-temperature, low-vapor pressure
non-aqueous electrolytes are being developed as an
inexpensive method for producing homogeneous and
fine-grained aluminum-based thin films for corrosion protection.
Electrochemical Processing of Nanostructural
Materials (Metallurgy Division): Electrochemical methods for
the synthesis and characterization of nanoscale magnetoresistive device architectures are being
examined with an emphasis on the use of surfactants and
segregation phenomena in controlling homo- and hetero-epitaxial
film growth.
Reaction Path Analysis in Multicomponent Systems
(Metallurgy Division): Costly experimental investigations
of bonding and reaction processes involving interdiffusion
at interfaces between metals, oxides, and vapors are
supplanted by models, based on thermodynamic data,
that predict the formation of transient phases and rates
of reaction in complex multicomponent systems.
Metals Processing projects with an especially strong focus
on areas which are of special interest to MSEL have evolved
to become part of other program areas such as Materials
for Microelectronics and Forming of Lightweight Materials.
Because processing plays such a basic role in determining the
properties and performance of metals, we expect this program to
continue providing a foundation for advanced metals technologies.
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Combinatorial Methods
Contact Information: Leonid A. Benderksy
The Combinatorial Methods Program develops new
measurement techniques and experimental strategies needed for
rapid acquisition and analysis of physical and chemical data
of materials by industrial and research communities. A
multi-disciplinary team from the NIST Laboratories participates
to address key mission-driven objectives in this new field,
including needed measurement infrastructure, expanded
capability, standards and evaluated data.
Measurement tools and techniques are developed to prepare
and characterize materials over a controlled range of physical
and chemical properties on a miniaturized scale with a high degree
of automation and parallelization. Combinatorial approaches
are used to validate measurement methods and predictive
models when applied to small sample sizes. All aspects of the
combinatorial process, from sample "library" design and library
preparation to high-throughput assay and analysis, are
integrated through the combinatorial informatics cycle for
iterative refinement of measurements. The applicability of
combinatorial methods to new materials and research problems is
demonstrated to provide scientific credibility for this new R&D paradigm.
One anticipated measure of the success of the program would be
more efficient output of traditional NIST products of
standard reference materials and evaluated data.
Through a set of cross-NIST collaborations in current
research areas, we are working to establish the infrastructure that
will serve as a basis for a broader effort in combinatorial research.
A Combinatorial Methods Working Group (CMWG)
actively discusses technical progress within NIST on
combinatorial methods through regular meetings. The technical areas
and activities of the CMWG are available in a brochure
"Combinatorial Methods at NIST" (NISTIR 6730). Within MSEL,
novel methods for combinatorial library preparation of
polymer coatings have been designed to encompass variations of
diverse physical and chemical properties, such as composition,
coating thickness, processing temperature, surface texture and
patterning. Vast amounts of data are generated in a few hours
that promote our understanding of how these variables affect
material properties, such as coatings wettability or phase
miscibility. Additional focus areas for both organic and inorganic
materials include multiphase materials, electronic materials,
magnetic materials, biomaterials assay, and materials structure
and properties characterization. State of the art on-line data
analysis tools, process control methodology, and data archival
methods are being developed as part of the program.
In order to promote communication and technology transfer
with a wide range of industrial partners, an
industry-national laboratories-university combinatorial consortium, the
NIST Combinatorial Methods Center (NCMC), is being organized
by MSEL. The NCMC will facilitate direct interactions
on combinatorial measurement problems of broad industrial
interest and efficient transfer of the methods developed to U.S. industry.
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Data Evaluation and Delivery
Contact Information: Ursula R. Kattner
Materials data are critical to the rapid and decentralized
design and manufacture of communication, transportation and
other devices, which characterize 21st century life. The goal of the
Data Evaluation and Delivery Program is to provide the producers
and users of materials with the means of fulfilling their
data requirements in the most efficient ways. This goal is
accomplished by providing improved access to materials
data, developing methods for transferring materials data across
the World Wide Web, providing protocols for data evaluation,
and enhancing the functionality of existing collections of
evaluated data. Much of this research is based on information
technology and includes: the development of a materials mark-up
language (MatML), the linkage of digitized crystallographic
information with full structure analysis in cooperation with the
International
Center for Diffraction Data and Fachinformationszentrum
(FIZ) Germany, and the production of phase diagrams through
the NIST/American Ceramics Society Phase Equilibria
Program. Other informatics available to the community are contained
in the Ceramics WebBook at the Ceramics Division Website.
The Ceramics WebBook provides links to other sources of
ceramic data and manufacturer's information, selected evaluated
data sets, structural ceramics and high temperature
superconductor databases, glossaries, and tools for analysis of ceramic materials.
Databases for metals will be developed on web pages in
the form of phase diagrams, deformation mechanism maps,
and simple - but useful - interactive calculations of
thermodynamic and mechanical properties. Annotation and interpretation
will be conducted by the Metallurgy Division.
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