Tasks one, two, and three of component one.
Component one,Task one
Prepare a 200- to 300-word history about the National Critical Technology (NCT) technical application your team has selected to solve a local or national problem.
A Car chassis is the frame of a car that gives it structural rigidity. They were originally made from wood and based off of coach design. This worked for the early cars of the late 1800s but as cars got faster the wooden frame was too weak by itself. At the start of the 20th century, steel and aluminum was incorporated into the chassis. This improved strength and design freedom. But a metal body on a wooden frame was the most common till about 1910.
In 1915 H.J. Hayes introduced a chassis with functionality. This had benefits like reduced cost and reducing noise and vibration. The same year Edward G. Budd proposed an all steel car. But this design required a lot of welds because stamping technology was still under development. This Idea was adopted by the Dodge Brothers and was the first volume production, all steel cars.
In 1922 Vincenza Lancia created the Lambda, a car with an "X-frame" chassis. This improved strength again.
In 1935, the body shop Carrozzeria Touring designed and developed a new frame design. It was made of small diameter, tubular pieces in Chrome- Molybdenum steel welded together. After World War II the main focus on design went toward performance, and steel was in low supply after the war, automotive companies went towards aluminum alloys.
In 1959 Maseratti sold the Tipo 60 race car. It incorporated a tubular frame of more than 200 tubes each only 10 to 15mm thick.
In the 1980s the primary design incorporated the frame as a complete piece with the roof included but the 1984 Pontiac Fiero used a frame that was assembled in pieces and then put together. These pieces were called sub frames and are used commonly today.
Bibliography: http://www.carbodydesign.com/articles/2005-04-13-chassis-history/2005-04-13-chassis-history.php Date researched: 10/27/09
Component 1, Task 2
Cite three detailed examples of research done in the past 3 to 5 years which focused on the NCT technical application your team selected.
In the project, they examined the mechanical properties of the Ti-6Al-4V alloy with varying amounts of B content. The cast and HIPed alloys with 0.05, 0.10 and 0.4 wt.% B additions were supplied by
Tamirisa and Miracle of AFRL, WPAFB. Microstructural observations indicate that the B additionreduces the as-cast grain size dramatically. Concomitantly, an increase in the yield and ultimate tensile strengths was observed. Fracture toughness measurements indicate a reduction in KIc values with increasing B content, owing primarily to the reduced grain size. Fatigue crack growth measurements show a gradual reduction in threshold for fatigue crack initiation. Fractographic analyses were conducted to
examine the micromechanical reasons for the observed trends. by
Dr. U. Ramamurty
Department of Metallurgy
Indian Institute of Science
Bangalore - 560 012, INDIA
in collaboration with
Indrani Sen, PhD Student, IISc
D. Miracle and S. Tamirisa
AFRL, Wright Patterson Air Force Base, Dayton, OH, USA
Norwood, Massachusetts echanical Testing is that part of engineering design, development, and
research that provides data about material properties. Testing is also
required during manufacturing to ensure that a material or product meets
some predefined specification. In particular, universal testing machines
measure the mechanical properties of materials in tension, compression,
bending, or torsion. Common properties of interest in tension
are offset yield strength, Young's modulus, tensile strength, and total
elongation. Results of tension tests are the basis for stress-strain diagrams (Fig.
1), from which all mechanical properties are derived. Atrue picture of the
stress-strain diagram can be seen only through accurate measurements. For
example, when the test results from one lab do not match those of another, it
means that the measurements of one or the other are not accurate: Either the operator
is not running the test properly, or the testing machine is not configured
properly. Testing machines are available in two
classes, hydraulic and electromechanical. The principal difference is the way
that the load is applied. For purposes of this article, only static and quasi-static machines are
considered. Accurate mechanical testing requires not only
familiarity with measurement systems, but also some understanding of the planning, execution,
and evaluation of experiments. Much experimental equipment is often "homemade,"
especially in smaller companies where
the high cost of specialized instruments cannot always
be justified. If the designer of the "homemade" equipment
does not carefully consider how the design
functions under test conditions, then the stress vs.
strain diagram may be in error.
*Member of ASM International
In an electromechanical machine (Fig. 3), a variable speed electric motor, gear reduction
system, and one, two, or four screws move the crosshead up or down. This motion loads the
specimen in tension or compression. A range of crosshead speeds can be achieved by
changing the speed of the motor. A microprocessor- based closed-loop servo system can
be implemented to accurately control the speed of the crosshead.
In general, the electromechanical machine is capable of a wider range of test speeds and longer
crosshead displacements, whereas the hydraulic machine is a more cost-effective solution for generating
higher forces. Sensors are at the heart of all mechanical testing
measurements. The test frame, power transmission, grips, and fixtures also affect the accuracy
and repeatability of sensors. If sensors are mounted in the wrong position, are heated up, or
are deformed by mounting bolts, they can introduce measurement errors.
Agood test engineer must have an excellent understanding of the sources of error that may be
introduced during a test. Before commencing any tests, the engineer should review the choice of sensors
and measurement instruments, keeping in mind the suitability and accuracy of each.
Knowing how to measure errors is critical to preventing them from creeping into results.
Modulus of plastic in flexure
ASTM D790 governs the determination of the flexural modulus of unreinforced and reinforced
plastics. ASTM D790 requires that a bar of rectangular cross section resting on two supports be
loaded by means of a loading nose midway between the supports.
Figure 3 depicts such a test setup. The supports and loading nose are shown in light blue. The
loading nose contacts the rectangular specimen at Point 4, and is directly connected to the load
" Weights and measures may be ranked among
the necessaries of life, to every
individual of human society. They enter
into the economical arrangements and daily
concerns of every family. They are
necessary to every occupation and human
industry; to every transaction of trade
and commerce. The knowledge of them . . .
is among the first elements of education,
and is often learnt by those who learn nothing
else, not even to read and write."
John Quincy Adams Fig. 1 - Astress vs. strain diagram.
In a hydraulic testing machine (Fig. 2), either a single- or dual-acting piston applies the load. Most
static hydraulic testing machines have a single-acting piston or ram. In a manually operated machine, the
operator adjusts the orifice of a pressure-compensated needle valve to control the rate of loading. In
a closed-loop hydraulic servo system, the needle valve is replaced by an electrically operated servo valve for precise control.
Report ID:PLS020A, Published: May 2000, Analyst: Melvin Schlechter
Report ID:PLS020A, Published: May 2000, Analyst: Melvin Schlechter
Component one, task three
Based on the research your team has done, explain how the NCT application chosen has advanced scientific knowledge.
Alloys have benefited science and the needs of people for centuries. Alloys make it possible to produce a metal to fit certain needs by combining metals with desired characteristics. The first alloy: bronze changed history by affecting the outcome of wars. In today's times however, alloys are still having an impact on our lives. New alloys are making it possible to conduct new experiments and reach new benchmarks in science. Metals like lithium-aluminum and Titanium are making it possible for new vehicles and components for the future. Alloys go beyond the restraints of the pure metals. It allows metals to be used in more situations than ever before.
Alloys have benefited science and the needs of people for centuries. Alloys make it possible to produce a metal to fit certain needs by combining metals with desired characteristics. The first alloy: bronze changed history by affecting the outcome of wars.
In today's times however, alloys are still having an impact on our lives. New alloys are making it possible to conduct new experiments and reach new benchmarks in science. Metals like lithium-aluminum and Titanium are making it possible for new vehicles and components for the future.
Alloys go beyond the restraints of the pure metals. It allows metals to be used in more situations than ever before.