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Progress of the Federal program for control of pollutant emissions from motor vehicles is summarized, through the 1968-1980 period. The standards mandated by the Clean Air Act have now been achieved. The future will see greater emphasis on maintaining the control of emissions from passenger cars in service, as opposed to more stringent emissions standards for new cars. More emphasis will also be placed on standards for highway vehicles other than passenger cars and on control of added pollutant types, such as particulate emissions from diesel powered vehicles.

It is known that internal combustion engines have low efficiency and produce air pollution. Among the less polluting fuels this work uses the natural gas. It is evaluated a bi-fuel Diesel engine, powered by Diesel oil and natural gas aiming at improving the overall efficiency. In the tested engine the energy comes from natural gas combustion. The Diesel oil just generates the pilot ignition for the combustion process. Diesel oil is replaced by natural gas, increasing so the efficiency of combustion. Initially, the engine was tested with Diesel oil to obtain reference parameters for their nominal characteristics. After that, tests were carried out with distinct proportions of Diesel oil and natural gas at different angles of injection progress. It was obtained the best performance for 22% of Diesel oil in relation to the maximum debit of the injector pump and 13 L/min of natural gas with original angle of injection progress (21º).

This paper describes the development of an analytical method to assess and optimize halfshaft joint angles to avoid excessive 3rd halfshaft order vibrations during wide-open-throttle (WOT) and light drive-away events. The objective was to develop a test-correlated analytical model to assess and optimize driveline working angles during the virtual design phase of a vehicle program when packaging tradeoffs are decided. A twelve degree-of-freedom (12DOF) system model was constructed that comprehends halfshaft dynamic angle change, axle torque, powertrain (P/T) mount rate progression and axial forces generated by tripot type constant velocity (CV) joints. Note: “tripot” and “tripod” are alternate nomenclatures for the same type of joint. Simple lumped parameter models have historically been used for P/T mount optimization; however, this paper describes a method for using a lumped parameter model to also optimize driveline working angles.

This paper describes the merits of manufacturing passenger car intake and exhaust manifolds from steel stampings or fabrications. Information on manufacturing methods, projected costs, as well as prototype work is presented. A review of successful current applications and potential future applications of fabricated manifolds concludes the paper.

Hat stiffened composite assemblies provide aircraft with a high strength to weight ratio structure. They are however, time consuming and difficult to produce. A new tooling method has been developed that looks promising for fabricating this type of assembly. This new method incorporates a flexible caul (flexcaul) and inflatable mandrels and can be incorporated with the existing bond mold. This method improves the shape and location of the hats while reducing the fabrication time

Magnesium parts can be fabricated by most of the standard metal working methods provided the process is adapted to the metal. Both casting and forming processes are routinely used to make magnesium parts on a production basis. Secondary operations are also standard practice for this industry. Described in this paper are some of these standard fabricating techniques and the modifications required.

The paper describes many of the methods of fabricating and finishing fiberboard parts for the automotive industry. Fabricating methods include die-cutting, crease bending, forming, fastening, and adhesive bonding. Finishing methods discussed are paint roll coating, spray painting, printing, and embossing. The equipment and tooling required are also described.

As the world is going through an evolutionary development in most of the science fields, there is an essential and exceptional demand for higher efficiency power generators to recover the thermal losses. Recently thermoelectric materials have attracted extensive attention for this purpose. The recent advancement in nanotechnology has a remarkable impact on thermoelectric materials development. This resulted in nano structured materials whose thermoelectric properties exhibit a great challenge to its bulk form, such as Silicon nanowires (SiNWs). Silicon nanowires are promising thermoelectric materials as they offer large reductions in thermal conductivity over bulk Si without significant decrease in the electrical conductivity. In the present work silicon nanowires have been implemented in fabricating a thermoelectric device which can be employed in different applications, such as engines, to recover part of the energy lost in these applications.

Concerning the fabrication of advanced components of dense silicon nitride, many methods of approach have been reported on in literature. To date, none of these attempts for the fabrication of turbine rotors has been considered feasible. The HIP process, it is believed, can offer an economically viable solution for fabrication of advanced ceramic components when the following reasons are considered: a) hot isostatic pressing is a well established technique. b) dense silicon nitride can be produced without any additives. c) fully isotropic dense silicon nitride is achieved. d) no reaction with capsule material. e) high M.O.R. values at high temperatures. f) consistently high Weibull m-module. g) very high creep resistance. The HIP process implies that even monolithic turbine rotors can be fabricated to final shape. The principle of the HIP process allows production of a large number of components simultaneously, thus offering possibilities for economic production on a large scale.

Familiarity with beryllium metal machining and handling characteristics places the material in favorable perspective with conventional materials. The stability, coefficient of expansion, and thermal conductivity of beryllium are very favorable to achieving and maintaining size control. Extensive use in the aerospace industry has assisted in development of allied processes that further enhance the achievements in fabrication techniques. This paper shows the evolution of fabrication considerations from procurement through completion of parts. Interim processes and surface treatments will be discussed, featuring some applications.

This paper discusses fabrication results experienced with HY-140 steel flight type pressure vessels. HY-140 steel is a recently developed quenched and tempered alloy (5Ni-CR-Mo-V) structural steel with a yield strength of 140,000 psi. Fabrication techniques applied, the tooling used, and the problems encountered are described in detail.

Tetra-Core is the name given to a fiber composite-material developed by the U.S. Army Aviation Materiel Laboratory, Fort Eustis, Va. This report discloses the initial studies conducted at the University of Kansas on Tetra-Core, including fabrication methods, analytical strength analyses, and experimental test results. The Tetra-Core composite is formed by stacking oriented, spaced-fiber lamina in a repeating -60, 0, +60 deg pattern. Layers are offset slightly as the stacking occurs to produce a tetrahedrally shaped element. An improved fabrication loom was conceived and tested. The loom concept is predicated on the fact that the intersection of two planes is a straight line. In the case of Tetra-Core, planes are formed by the buildup of lamina, intersecting to produce tetrahedrally shaped elements. The straight lines formed at these intersections are at an angle of 35 deg 15 min from the vertical.

The following paper has been prepared to describe the procedures used to fabricate and assemble a lightweight demonstration vehicle, built under contract to Ford Motor Company. G.F.R.P. (Graphite Fiber Reinforced Plastic), the specified material for the major body components, made it necessary to combine state-of-the-art aerospace manufacturing methods with current automotive prototype technology to ensure successful completion of the project. Major areas of emphasis include; master tooling aid development, high temperature epoxy molds, component fabrication, component subassembly and body assembly. These areas will be discussed in detail, along with the completion and final assembly of the lightweight vehicle.

Stringent emission standards are driving the development of diesel-fuel injection concepts to mitigate in-cylinder formation of particulates. While research has demonstrated significant reduction in particulate formation using micro-orifice technology, implementation requires development of industrial processes to fabricate micro-orifices with diameters as low as 50 μm and with large length-to-diameter ratios. This paper reviews the different processes being pursued to fabricate micro-orifices and the advanced techniques applied to characterize the performance of micro-orifices. The latter include the use of phase-contrast x-ray imaging of electroless nickel-plated micro-orifices and laser imaging of fuel sprays at elevated pressures. The experimental results demonstrate an industrially viable process to create small uniform orifices that improve spray formation for fuel injection.

Conventional materials like steel, brass, aluminum etc will fail without any indication, cracks initiation, propagation, will takes place with a short span. Now-a-days to overcome these problem, conventional materials are replaced by hybrid composite material. Not only have this conventional material failed to meet the requirement of high technology applications, like space applications and marine applications and structural applications in order to meet the above requirements new materials are being searched. Hybrid composites materials found to the best alternative with its unique capacity of designing the materials to give required properties and light weight. This paper aims to preparing hybrid composite using artificial fibers. Epoxy as resin and glass fiber as fiber for artificial hybrid composite to make a laminate for preparing leaf spring.

Composites materials are substituting constituents for traditional materials due to their remarkable properties, and the addition of nanoparticles gives a new development in the material domain. The nanoparticles influence on fabrication and machinability investigation study is essential as the composites to be used in applications like automotive and aerospace. The current study investigates the machinability characteristics of Al2219 based metal composites reinforced with nanoparticles of SiN/MoS2. Al2219- reinforcements (SiN and MoS2) composites are fabricated by the method of stir casting. Four different compositions (Al2219/SiN (2 wt% and 4 wt%), , Al2219/2 wt.% SiN/ 2 wt.% MoS2, Al2219/2 wt.% MoS2) are fabricated by varying the different weight percentages of nanoparticles reinforcements. An attempt is made to study the investigation analysis of force, surface roughness, and tool wear using CNC machine lathe to consider the effect of cutting speed, cutting depth, and samples.

In the present experimental investigation magnesium based alloy was prepared by mixing magnesium powder and aluminium powder in the ratio 65:35. The prepared magnesium alloy is used as the matrix material. Metal matrix composites were prepared by stir casting route. The composite was prepared by reinforcing 50 nm alumina nanoparticle so that the final composite contains 5, 10 and 15 wt.% alumina. Mechanical properties such as tensile strength, yield strength, impact strength and hardness were evaluated. Significant improvement was observed in impact strength and hardness value. The result showed that magnesium alloy with 5 wt.% alumina nanoparticle has a maximum impact strength of 25.2 J and hardness value 63.86 Hv respectively. Tensile strength and yield strength shows marginal increase in value.

Metal matrix composites were produced by the PRIMEX™ pressureless metal infiltration process. Properties of the composites were determined as a function of particulate loading, filler type, alloy chemistry, and test temperature. Using the property data, a generic brake caliper bridge geometry was designed and modeled. The results of the modeling suggested that composite caliper bridges can be equivalent in stiffness to ductile iron components at only 43% of the mass, and equivalent in stiffness to aluminum components at only 60% of the mass. In addition, composites containing unreinforced regions (i.e., areas without ceramic particulates) were fabricated to facilitate drilling and tapping at attachment locations. The strength of the threads in these regions was evaluated and compared with thread strengths in iron, Al alloy, and monolithic metal matrix composite.