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Abstract The paper presents a complete description of the design and manufacturing of a Carbon Fiber/epoxy mold with an embedded Carbon Fiber resistor heater, and the mold performances in terms of its surface temperature distribution and thermal deformations resulting from the heating. The mold was designed for manufacturing aileron skins from Vacuum Bag Only prepreg cured at 135°C. The glass transition temperature of the used resin-hardener system was about 175°C. To ensure homogenous temperature of the mold working surface in the course of curing, the Carbon Fiber heater was embedded in a layer of a highly heat-conductive cristobalite/epoxy composite, forming the core of the mold shell. Because the cristobalite/epoxy composite displayed much higher thermal expansion than CF/epoxy did, thermal stresses could arise due to this discrepancy in the course of heating.

The present study looks into different possibilities for tribological optimization of the piston/bore system in heavy duty diesel engines. Both component rig tests and numerical simulations are used to understand the roles of surface specifications, ring pack, and lubricant in the piston/bore tribology. Run-in dynamics, friction, wear and combustion chamber sealing are considered. The performance of cylinder liners produced using a conventional plateau honing technology and a novel mechanochemical surface finishing process - ANS Triboconditioning® - is compared and the importance of in-design “pairing” of low-viscosity motor oils with the ring pack and the cylinder bore characteristics in order to achieve maximum improvement in fuel economy without sacrificing the endurance highlighted. A special emphasis is made on studying morphological changes in the cylinder bore surface during the honing, run-in and Triboconditioning® processes.

Laser machining is an effective material removal process for types of materials which are difficult to machine mechanically, such as hardened alloys, ceramics, and composites. Since laser machining is a thermal process, its effectiveness depends on the thermal rather than the mechanical properties of a material. This paper discusses a concept for performing three-dimensional (3-D) laser machining using two laser beams. This concept aims at improving the material removal rate and energy efficiency of laser machining. Furthermore, the kinematic aspects of 3-D laser machining are discussed. Results for 3-D laser machining of metals, ceramics and composites are presented and compared with conventional machining methods.

The National Soil Dynamics Laboratory and Auburn University are developing tools and methods to help farmers make correct decisions about how to best avoid compacting their soil. Four areas of research are being integrated into an overall soil compaction model. These areas are the measurement of soil-tire interface stresses, the measurement of soil stresses in the soil profile, the development of constitutive stress-strain relationships for agricultural soils, and the development of analytical and finite element soil compaction models that can accurately predict the depth and degree of excessive soil compaction.

From investigating the porosity and graphite effects on sintered bronze for wet clutch applications, it is clear that elasticity, as determined by the porosity and the graphite content, is important for both the friction coefficient and the power absorbing capacity. The apparent elastic modulus values, measured by a compression test of clutch disks, show a very good correlation with performances of various wet friction materials (sintered bronze, paper, graphitics and elastomerics) in both an inertia-brake type clutch testing machine and also on the full-size powershift transmission bench. The lower elastic modulus material has the higher friction coefficient and the better energy/power absorbing capacity. Effects of the material pores, the oil-groove patterns and also the material deterioration on friction performances and hot-spot size are discussed in conjunction with apparent elastic modulus.

Abstract Cavitation erosion caused by high-frequency vibrating walls can appear in the cooling circuit of internal combustion engines along the liners. The vibrations caused by the mechanical forces acting on the crank drive can lead to temporary regions of low pressure in the coolant with local vapor formation, and vapor collapse close to the liner walls leads to erosion damage, which can strongly reduce the lifetime of the entire engine. The experimental investigation of this phenomenon is so time consuming and expensive, which it is usually not feasible during the design phase. Therefore, numerical tools for erosion damage prediction should be preferred. This study presents a numerical workflow for the prediction of cavitation erosion damages by coupling a three-dimensional (3D) Multi-Body-Dynamic (MBD) simulation tool with a 3D Computational Fluid Dynamics (CFD) solver.

Differences, where they exist, are shown in Appendix A. This SAE Standard establishes a classification of materials intended for the manufacture of piston rings based on mechanical properties and the stresses that these materials are capable of withstanding. This document applies to the manufacture of piston rings up to and including 200 mm diameter for reciprocating internal combustion engines. It also applies to piston rings for compressors working under similar conditions.

The purpose of this SAE Information Report is to provide concepts for rational selection and application of materials for Rollover Protective Structures (ROPS) and Falling Object Protective Structures (FOPS) and to provide information about the properties that should be considered in selecting and utilizing material in protective structures. While other materials could conceivably be used successfully, this report is limited to a consideration of steel with discussion on its mechanical properties and processing characteristics. Emphasis is placed on the toughness aspect (ability to resist brittle fracture) as this property is of paramount importance to structure integrity. It is emphasized that specific values for material properties have relevance to performance only in conjunction with specific design considerations such as structure size or weld joint detail and location.

The purpose of this SAE Information Report is to provide concepts for rational selection and application of materials for Rollover Protective Structures (ROPS) and Falling Object Protective Structures (FOPS) and to provide information about the properties that should be considered in selecting and utilizing material in protective structures. While other materials could conceivably be used successfully, this report is limited to a consideration of steel with discussion on its mechanical properties and processing characteristics. Emphasis is placed on the toughness aspect (ability to resist brittle fracture) as this property is of paramount importance to structure integrity. It is emphasized that specific values for material properties have relevance to performance only in conjunction with specific design considerations such as structure size or weld joint detail and location.

The purpose of this information report is to provide concepts for rational selection and application of materials for Rollover Protective Structures (ROPS) and Falling Object Protective Structures (FOPS) and to provide information about the properties that should be considered in selecting and utilizing material in protective structures. While other materials could conceivably be used successfully, this report is limited to a consideration of steel with discussion on its mechanical properties and processing characteristics. Emphasis is placed on the toughness aspect (ability to resist brittle fracture) as this property is of paramount importance to structure integrity. It is emphasized that specific values for material properties have relevance to performance only in conjunction with specific design considerations such as structure size or weld joint detail and location.

The compositions and mechanical properties are only suggested to ensure good weldability and good formability in conjunction with control of mechanical properties. The particular design must be considered to ensure that the materials selected are compatible with the design. The indicated properties are intended to assure that the ROPS or FOPS will have meaningful resistance to brittle fracture. The impact toughness requirement is the conventional Charpy V Notch evaluation: it is primarily a quality control check and the indicated temperature does not directly relate to operating conditions. Three steel product categories are covered: hollow structural members, plates, bars and shapes, and castings.

The purpose of this SAE Recommended Practice is to specify dimensions for loader straight cutting edge cross sections without holes and with bolt holes for mounting bolt-on teeth and tooth adaptors on loader buckets described by SAE J731. This recommended practice is intended to supplement SAE J1303 and SAE J1304 with cross sections for heavier duty applications, by identifying larger blunts, greater bevel angles, larger bolt holes, and greater bolt spacing.

This SAE Parts Standard provides dimensional and quality assurance requirements for M6 through M36 metric sizes of studs in the following configurations in materials needed for ship system applications: a Continuous thread studs in M thread profile. b Double end studs—clamping type (also called bolt-studs) where both ends are of the same thread series but different lengths (M thread profile).

This SAE Parts Standard provides dimensional and quality assurance requirements for M6 through M36 metric sizes of studs in the following configurations in materials needed for ship system applications: a Continuous thread studs in M thread profile. b Double end studs—clamping type (also called bolt-studs) where both ends are of the same thread series but different lengths (M thread profile).

It applies to reports of Surface Vehicles and Machinery Technical Committees only. Aerospace technical reports are covered by editorial practices of the Aerospace Council. Close adherence to this recommended practice by technical committees of SAE will help to assure uniform technical reports. Should questions on format, style, or other matters pertaining to the organization and editorial practices of technical reports be raised within technical committees of the Technical Board, they should be referred to the Chairman of the Publications Advisory Committee for interpretation or for discussion by the full Publications Advisory Committee.

This SAE Recommended Practice applies to off-road, self-propelled work machines defined in SAE J1116 JUN81.

This SAE Part Standard covers selected inch dimensioned tapping screws and metallic drive screws manufactured in accordance with American Society for Mechanical Engineers dimensional standards. This SAE standard covers material most often used in ship systems and equipment but its use may be applied wherever fasteners of the covered materials are used. This standard permits the fasteners to be identified and ordered by a part or identifying number (PIN) as defined in this standard.