An enormous economic loss, as well as a waste of natural resources, is incurred world-wide as a result of wear of components and tools. Any effort expended in an attempt to reduce this loss is indeed worthwhile. The purpose of this SAE Information Report is to present the current state of knowledge of abrasive wear. This report, therefore, covers wear, or the undesired removal of metal by mechanical action, caused by abrasive particles in contact with the surface. It does not concern metal-to-metal wear or wear in the presence of an abrasive free lubricant. Abrasive wear occurs when hard particles, such as rocks, sand, or fragments of certain hard metals, slide or roll under pressure across a surface. This action tends to cut grooves across the metal surface, much like a cutting tool. Abrasive wear is of considerable importance in any part moving in relation to an abrasive. Tools in contact with the ground, such as plows, cultivators, scraper and bulldozer blades, are intended to operate in abrasives. Machines for processing ores such as crushers and for grinding of natural minerals such as ball mills are also subjected to abrasive wear. Contact with abrasives by many other machinery components may not be a normal circumstance, but, since it may inadvertently occur, must be considered. Increased hardness usually increases wear resistance but also increases brittleness, which can cause fracture of the tool in rocky soils. Thus, the selection of a suitable material for use in a variety of abrasive conditions is necessarily a compromise between wear and brittle fracture resistance. This report presents present day information on the fundamentals, testing methods and specific solutions for abrasive wear problems. The limited information reflects the current lack of knowledge on this subject. However, it is a starting point. Further work is necessary to develop general design information.

Metals Technical Committee

Fe-Mn-Al-C Alloy Steels – A New Armor Class

2017-01-17033/28/2017

Fe-Mn-Al-C steel alloys have been previously studied for their potential as an alternative steel alloy for Rolled Homogeneous Armor (RHA). Prior examination of the material system has shown promise in this capacity due to the high strength and reduced density of Mn steels as compared to RHA. The prior tested materials were both wrought and cast versions but were all less than an inch in thickness. The alloy is once again being examined, but this time in thicker wrought plate. The aim of the current body of work is to develop a Military Specification (MIL-SPEC) for this new class of ballistically capable material. For industry and communities interested in such material development, the purpose of this paper, then, is to provide a summary of the processing parameters, the prior ballistic and dynamic material testing, cutting and welding approaches, and the extent of progress on industrial sized thick plate development.

Howell, Ryan A., Gerth, Richard

Columbium (Niobium) Alloy Bars, Rods, and Extrusions 10Hf - 1.0Ti, Recrystallization Annealed

AMS7857C (Current)

1/11/2017

This specification covers a columbium (niobium) alloy in the form of bars, rods, and extrusions.

AMS G Titanium and Refractory Metals Committee

Steel Sheet, Strip, and Plate 0.80Cr - 1.8Ni - 0.25Mo (0.49 - 0.55C) Annealed

AMS6396F (Historical)12/19/2015

This specification covers an aircraft-quality, low-alloy steel in the form of sheet, strip, and plate.

AMS E Carbon and Low Alloy Steels Committee

A Theoretical Approach of UNIT (Unified Nuclear Integral Technology) Propulsion and its Potential for Future Applications in Space Exploration

2015-01-90049/1/2015

Space exploration is the present inevitable challenge for researchers. Various theoretical propulsion concepts have been evolved over the past years for space missions. Their potential remains as a key factor for the spacecraft to travel deeper into space in a shorter mission duration. The propulsion concept UNIT is an integrated nuclear propulsion technique that provides high entry, descent and landing (EDL) performance in such short duration to conquer other galaxies. This paper describes the theoretical approach of the UNIT propulsion system in detail. UNIT produces the highest energy possible by consuming nuclear fuel and possess the highest potential that opens new opportunities for space exploration. The principle is that the neutrons from the fusion are deliberately allowed to induce fission. It uses National Ignition Facility's laser beam for inertial confinement fusion followed by utilizing the power from tubular solid fuel cell. Thus, the net thrust is produced from the expansion of the combined plasma of the nuclear fusion and nuclear fission reactions through the nozzle.

Dran, Sarath Ramachan

Innovative, Low-CTE, Lightweight Structures with Higher Strength

TBMG-21407

2/1/2015

A series of lightweight (density below 2.0 gm/cm3) composites has been manufactured that have controllable properties. The core composite has been improved to provide higher strength (similar to aluminum), extremely low density, receptivity to exterior coatings, and highly designable properties. The composite is made in days, is machinable and formable, can be joined/threaded, can be exposed to various environments (temperature, radiation), and is easily made into many parts. Lightweight mirrors for space and IR applications are extremely important. The goal of this work was to create lightweight multifunctional composites for replacement of titanium, beryllium, Invar, aluminum, rubber, and graphite epoxy for structural, mirror, and non-structural components. The key characteristics of this tailorable composite are low density, high stiffness (up to 25 MSI modulus), variable/low coefficient of thermal expansion (CTE) (2 to 7 ppm/°C), high temperature refractory materials and variable thermal conductivity. The composites are easily made (time to completion of 7 to 10 days), joinable, threadable, machinable to 80 mils, durable to resist FOD (foreign object damage), ductile enough to behave like a metal, and relatively low in cost.

Tribological Characteristics of Yttria Stabilized Zirconia Nanolubricants

2014-01-279010/13/2014

Nanolubricants are suspensions of nanoparticles in base fluids, a new challenge for thermal sciences provided by nanotechnology. The objective of this work is to analyze the thermal and tribological properties of yttria stabilized zirconia (YSZ) nanolubricants. Nanosized YSZ particles were prepared by milling YSZ (10μm) in a planetary ball mill equipped with vials using tungsten carbide balls. After 40 hrs, milled YSZ nanoparticles of sizes ranging from 70-90nm were obtained. The nanoparticles were characterized by Energy Dispersive X-ray analysis (EDXA), Scanning Electron microscope (SEM), Transmission Electron Microscope, Thermo Gravimetric-Differential Scanning Calorimeter and non contact 3D surface profilometer and the images of the same were obtained. The heat transfer properties of automotive engine lubricants were determined by utilization of measured thermal conductivity, viscosity index, density, flash point, fire point and pour point, which revealed that lubricants with additive constituents have a significant effect on the resultant heat transfer characteristics of the lubricants. The YSZ nanoparticles incorporated lubricants were evaluated for their potentials as effective solid lubricants at room temperature by using ball-on-disk tribometer. The lubricant without nanoparticles has a co-efficient of friction of 0.08-0.1 and a wear rate in the order of 10-4 mm3/Nm, while the lubricant with yttria stabilized zirconia nanoparticles exhibits a steady state co-efficient of friction of less than 0.07 and a wear rate in the order of 10−6 mm3/Nm at room temperature. Scratches and furrows are considered as the dominating wear mechanism of the disc applied with lubricants. However, for the disc applied with YSZ nanolubricants, the formation and effective spreading of the YSZ lubricating films are the most important factor to reduce the friction and wear rate.

Ganapathy Pandian, Sakthinathan

Advanced Materials for Aerospace and Space Applications

2014-01-22339/16/2014

Constant swirls of innovative ideas are starting to push composites and hybrid metal-composite components for use in an ever expanding circle of products. Recent discoveries of Graphene/Au composites have invigorated innovations for its application to aerospace and space products. Attributes such as a low CTE, stiffness, and light weight attract other manufacturers of smaller products to use composites for enhanced performance and durability. The uses and economics of composites is an enormously broad subject. Examples of composite materials will be described in this paper to provide samples of applications selected for their far reaching potential to enhance product performance. Examples will also be presented to explain the application of carbon based composites where the product performance or application would not be possible without special materials. This paper will also describe emerging materials such as graphene and some of its applications to enhance the performance of current technologies It is easy become enamored with the composite big parts built for trains, planes, automobiles, ships, and wind turbine blades. We sometimes forget that there is a world of composites that exists outside these highly visible products where composites materials are contributing in substantial ways to other product's improvement. Many times the use of composites is integrated into the larger products in the form of components where tribology is critical to performance or coatings are needed to provide thermal protection.

Bullen, George Nicholas

Calculation of Electron Vacancy Number in Superalloys

AS5491C (Historical)

10/25/2013

This SAE Aerospace Standard (AS) establishes a uniform procedure for calculation of electron vacancy numbers in superalloys. It is intended for use by suppliers of raw materials and parts, typically castings, for which control of electron vacancy number is required by the raw material specification.

AMS F Corrosion Heat Resistant Alloys Committee

Advanced Materials and Fabrication Techniques for the Orion Attitude Control Motor

TBMG-163305/1/2013

Rhenium, with its high melting temperature, excellent elevated temperature properties, and lack of a ductile-to-brittle transition temperature (DBTT), is ideally suited for the hot gas components of the ACM (Attitude Control Motor), and other hightemperature applications. However, the high cost of rhenium makes fabricating these components using conventional fabrication techniques prohibitive. Therefore, near-net-shape forming techniques were investigated for producing cost-effective rhenium and rhenium alloy components for the ACM and other propulsion applications.

Estimating Foreign-Object- Debris Density From Photogrammetry Data

TBMG-161444/1/2013

Within the first few seconds after launch of STS-124, debris traveling vertically near the vehicle was captured on two 16-mm film cameras surrounding the launch pad. One particular piece of debris caught the attention of engineers investigating the release of the flame trench fire bricks. The question to be answered was if the debris was a fire brick, and if it represented the first bricks that were ejected from the flame trench wall, or was the object one of the pieces of debris normally ejected from the vehicle during launch. If it was typical launch debris, such as SRB throat plug foam, why was it traveling vertically and parallel to the vehicle during launch, instead of following its normal trajectory, flying horizontally toward the north perimeter fence?

Engineered Tribological Composites

R-40111/30/2011

Roy Cox provides readers with a thorough presentation of the topic, beginning with the earliest work on brakes by Frood in the early 1900s and friction studies by daVinci in the 1400s. From there, details about the processes of wear and the components of tribological systems are presented. Methods of manufacturing friction materials are described, and the elements of friction material are detailed—binders, fibers, abrasives, and lubricants. A large portion of the book delves deeply into materials for binders, resins, fibers, abrasives, lubricants, and fillers, providing background on the various materials, their pros and cons, and numerous ways they can be applied to friction systems. Much of this discussion focuses on the compositional makeup and effects of ingredients as they relate to the wear and friction performance of the final product. Readers will gain a solid background about tribology, as well as a solid understanding of matrices, fibers and additives that make up engineered tribological composites. They will learn how manufacturing affects these composites, along with how friction and wear affect those materials. They will gain a better understanding of which materials provide the optimum balance of cost, friction and wear for various applications, enabling them to better create and apply engineered tribological composites for whatever application is at hand.

Cox, Roy

Molybdenum Disulfide Coating, Thin Lubricating Film, Impingement Applied

AMS2526A (Historical)8/10/2011

This specification covers a coating consisting of finely-powdered molybdenum disulfide in a heat-resistant inorganic binder applied to parts.

AMS B Finishes Processes and Fluids Committee

Improved Rare-Earth Emitter Hollow Cathode

TBMG-91542/1/2011

An improvement has been made to the design of the hollow cathode geometry that was created for the rare-earth electron emitter described in “Compact Rare Earth Emitter Hollow Cathode” (NPO-44923), NASA Tech Briefs, Vol. 34, No. 3 (March 2010), p. 52. The original interior assembly was made entirely of graphite in order to be compatible with the LaB6 material, which cannot be touched by metals during operation due to boron diffusion causing embrittlement issues in high-temperature refractory materials. Also, the graphite tube was difficult to machine and was subject to vibration-induced fracturing.

Columbium (Niobium) Alloy Bars, Rods, and Extrusions 10Hf - 1.0Ti, Recrystallization Annealed

AMS7857B (Historical)6/17/2008

This specification covers a columbium (niobium) alloy in the form of bars, rods, and extrusions.

AMS G Titanium and Refractory Metals Committee

Columbium (Niobium) Alloy Bars, Rods, and Wire 10W - 2.5Zr Recrystallized

AMS7855C (Historical)6/17/2008

This specification covers a columbium alloy in the form of bars, rods, or wire.

AMS G Titanium and Refractory Metals Committee

Tungsten Carbide-Cobalt Powder Sintered and Crushed

AMS7880C (Historical)3/13/2007

This specification covers tungsten carbide-cobalt in the form of powder.

AMS B Finishes Processes and Fluids Committee

A Test Method for Quantifying Residual Stress Due to Heat Treatment in Metals

2006-01-03194/3/2006

Quantification of residual stresses is an important engineering problem impacting manufacturabilty and durability of metallic components. An area of particular concern is residual stresses that can develop during heat treatment of metallic components. Many heat treatments, especially in heat treatable cast aluminum alloys, involve a water-quenching step immediately after a solution-treatment cycle. This rapid water quench has the potential to induce high residual stresses in regions of the castings that experience large thermal gradients. These stresses may be partially relaxed during the aging portion of the heat treatment. The goal of this research was to develop a test sample and quench technique to quantify the stresses created by steep thermal gradients during rapid quenching of cast aluminum. The development and relaxation of residual stresses during the aging cycle was studied experimentally with the use of strain gauges. Experimental and modeling results will be discussed in the development of the residual stress test casting.

Godlewski, Larry A., Su, Xuming, Allison, John E., Gustafson, Peter, Pollock, Tresa M.

Factors Affecting Tensile Properties of Castings

2004-01-10213/8/2004

The basic data on the mechanical properties of a casting are frequently obtained from a tensile test, in which a suitable specimen machined from the casting is subjected to increasing axial load until it fractures. The engineering tension test is widely used by casting manufacturers as an acceptance test for customer specifications. However, tensile bars machined from castings often provide undesirable information, thereby leading one to question the part integrity. This paper, therefore, discusses the various factors that affect tensile properties obtained from specimens machined from actual castings. These factors include: 1 Type of casting process 2 Wall thickness of castings 3 Microstructure 4 Size and distribution of inclusions in a tensile bar 5 Type and distribution of porosity in a tensile bar 6 Size and shape of tensile bar 7 Location of tensile bar in a casting Results from this investigation indicate that achieving undesirable tensile properties do not necessarily indicate that a part would not perform its intended function satisfactorily.

DasGupta, Rathindra, DasGupta, Sumantra, Brown, Craig

High-Strength, Hot-Rolled Steel Bars

J1442_200309 (Current)

9/24/2003

This SAE Recommended Practice covers two levels of high strength structural low-alloy steel bars having minimum Yield Points of 345 MPa (50 ksi) and 450 MPa (65 ksi). The two strength levels are 345 and 450 MPa or 50 and 65 ksi minimum yield point. Different chemical compositions are used to achieve the specified mechanical properties. In some cases there are significant differences in chemical composition for the same strength level, depending on the fabricating requirements. It should be noted that although the mechanical properties for a steel grade sourced from different suppliers may be the same, the chemical composition may vary significantly. The fabricator should be aware that certain compositional differences may effect the forming, welding, and/or service requirements of the material. It is therefore recommended that the fabricator consult with the producer to understand the effect of chemical composition. The products within the scope of this document include bars of the following types and sizes: Rounds, squares, and hexagons of all sizes (cut length only), flats 5.2 mm (0.203 in) and greater in thickness but not greater than 150 mm (6 in) wide, and flats greater than 5.8 mm (0.229 in) thick and over 150 mm (6 in) to 204 mm (8 in) wide. This document previously covered plates, structural shapes, and bar size shapes of Grades 290A, 345A, 415A, 450A, 345W, 345F, 415F, 485F, and 550F as well as bars of Grades 290A, 415A, and 345W. These products are no longer covered; requirements for these products and grades can be found in ASTM Specifications as follows in Table 1: Product Previous SAE Grade ASTM Specification/Grade Plates, Structural Shapes, Bar Size Shapes, Bars 290A A 572/A 572M, Grade 42 Plates, Structural Shapes, Bar Size Shapes 345A A 572/A 572M, Grade 50 Plates, Structural Shapes, Bar Size Shapes, Bars 415A A 572/A 572M, Grade 60 Plates, Structural Shapes, Bar Size Shapes 450A A 57/A 572M, Grade 65 Plates, Structural Shapes, Bar Size Shapes, Bars 345W A 588/A 588M Plates 345F A 656/A 656M, Grade 50 Plates 415F A 656/A 656M, Grade 60 Plates 485F A 656/A 656M, Grade 70 Plates 550F A 656/A 656M, Grade 80 TABLE 1 EQUIVALENT ASTM SPECIFICATIONS

Metals Technical Committee

Better VPS Fabrication of Crucibles and Furnace Cartridges

TBMG-12168/1/2003

An experimental investigation has shown that by (1) vacuum plasma spraying (VPS) of suitable refractory metal alloys on graphite mandrels, and then (2) heat-treating the VPS alloy deposits under suitable conditions, it is possible to fabricate improved crucibles and furnace cartridges that could be used at maximum temperatures between 1,400 and 1,600 °C and that could withstand chemical attack by the materials to be heated in the crucibles and cartridges. Taken by itself, the basic concept of fabricating furnace cartridges by VPS of refractory materials onto graphite mandrels is not new; taken by itself, the basic concept of heat treatment of VPS deposits for use as other than furnace cartridges is also not new; however, prior to this investigation, experimental crucibles and furnace cartridges fabricated by VPS had not been heat treated and had been found to be relatively weak and brittle. Accordingly, the investigation was directed toward determining whether certain combinations of (1) refractory alloy compositions, (2) VPS parameters, and (3) heat-treatment parameters could result in VPS-fabricated components with increased ductility.

Tungsten Sheet and Strip

AMS7899 (Current)12/16/2002

AMS G Titanium and Refractory Metals Committee

Deforming Fibrous Insulating Tiles To Fit Curved Surfaces

TBMG-101012/1/2002

A curved tile of refractory silica-fiber-based or alumina-fiber-based thermal-insulation material can be formed from an initially flat billet in a process that includes pressing against a curved mold surface during heating. The mold or tile curvature can be concave or convex. Curved tiles are needed for thermal protection of curved surfaces of spacecraft reentering the terrestrial atmosphere; curved thermal-protection tiles may also be useful on Earth in some industrial applications.

Tungsten Carbide Powder, Cobalt Coated

AMS7878C (Historical)8/20/2002

This specification has been declared "NONCURRENT" by the Aerospace Materials Division, SAE, as of March 1994. It is recommended, therefore, that this specification not be specified for new designs.

AMS F Corrosion Heat Resistant Alloys Committee

Tungsten Forgings, Pressed, Sintered, and Forged

AMS7897C (Historical)7/25/2002

This specification covers tungsten in the form of forgings produced from billets processed by isostatically cold pressing, utilizing hydrogen reduced tungsten powder, and high-temperature sintering.

AMS G Titanium and Refractory Metals Committee

Tungsten Sheet, Strip, Plate, and Foil, Pressed, Sintered, and Wrought

AMS7898D (Current)7/23/2002

This specification covers tungsten in the form of pressed, sintered, and wrought sheet, strip, plate, and foil.

AMS G Titanium and Refractory Metals Committee

Calculation of Electron Vacancy Number in Superalloys

AS5491B (Historical)

3/15/2002

This Aerospace Standard establishes a uniform procedure for calculation of electron vacancy numbers in superalloys. It is intended for use by suppliers of raw materials and parts, typically castings, for which control of electron vacancy number is required by the raw material specification.

AMS F Corrosion Heat Resistant Alloys Committee