Browse Topic: Chromium

Items (263)

Wear and Friction of PTFE and PEEK Coated Cast Iron Piston Ring

2022-01-038003/29/2022

In engine 30% of the total energy is lost due to the friction between piston ring and cylinder liner due to their constant rubbing motion. A piston that reciprocates at high speeds has piston rings that constantly scrape against the wall leading to high frictional losses within the engine. The engine has to work against this resistance to provide the required power, and hence it will consume more fuel. For this reason, material used for these components is more crucial. Reduction of surface friction between moving parts in order to increase overall efficiency can be achieved by suitable coating. The most commonly used piston rings are coated with chromium layers that are electroplated which is being replaced by chrome plating. Low coefficient of friction (COF) and high wear resistance can be achieved by self-lubricating coating of PTFE and PEEK polymer-based composite coatings. Experimental results showed that the PEEK and PTFE coating performed better in terms of friction and wear

Rajendran, R.

Steel, Bars, Forgings, and Mechanical Tubing 0.50Cr - 0.55Ni - 0.20Mo (0.18 - 0.23C) (SAE 8620)

AMS6274S (Current)

07/23/2021

This specification covers an aircraft-quality, low-alloy steel in the form of bars, forgings, mechanical tubing, and forging stock.

AMS E Carbon and Low Alloy Steels Committee

Product Analysis - Permissible Variations from Specified Chemical Analysis of a Heat or Cast of Steel

J409_202107 (Current)

07/15/2021

Supplementary to the heat or cast analysis, a product analysis may be made on steel in the semifinished or finished form. For definitions and methods of sampling steel for product chemical analysis, refer to SAE J408. A product analysis is a chemical analysis of the semifinished or finished steel to determine conformance to the specification requirements. The range of the specified chemical composition is normally expanded to take into account deviations associated with analytical reproducibility and the heterogeneity of the steel. Individual determinations may vary from the specified heat or cast analysis ranges or limits to the extent shown in Tables 1 through 5. The several determinations of any element in a heat or cast may not vary both above and below the specified range except for lead. Tables 1 through 5 provide permissible limits for various steel forms and composition types. For rephosphorized and resulfurized steels, the product analysis tolerance limits are not applicable

Metals Technical Committee

Product Analysis - Permissible Variations from Specified Chemical Analysis of a Heat or Cast of Steel

J409_202107-TEST-REC (Historical)07/15/2021

Metals Technical Committee

Steel Bars and Forgings, 0.25Mo (0.35 - 0.40C) (SAE 4037)

AMS6300H-TEST-REC (Historical)10/19/2020

This specification covers an aircraft-quality, low-alloy steel in the form of bars, forgings, and forging stock.

AMS E Carbon and Low Alloy Steels Committee

Steel Bars and Forgings, 0.25Mo (0.35 - 0.40C) (SAE 4037)

AMS6300H (Current)

10/19/2020

This specification covers an aircraft-quality, low-alloy steel in the form of bars, forgings, and forging stock.

AMS E Carbon and Low Alloy Steels Committee

Vanadium A Green Metal Critical to Aerospace and Clean Energy

20AERP08_0208/01/2020

In the 1960s, the world's leading aerospace engineers at Lockheed's Skunk Works facility faced an extraordinarily difficult engineering challenge: how to design a successor to the U-2 spy aircraft, which had proven increasingly vulnerable to advanced Soviet anti-aircraft systems. Among other capabilities, the next-generation aircraft they were to design required an ability to cruise at a sustained speed of Mach 3+, operate at altitudes exceeding 80,000 feet, and feature as low a radar cross section as possible. Given the technologies of the day - slide rules were still used by engineers for most calculations - it was a daunting task. One of the key hurdles was designing and machining components of the jet's outer skin such that it could handle temperatures from aerodynamic friction and continuous engine operation as high as 1,050 °F. The answer: titanium-based alloys that contained the metal vanadium. When added to titanium, vanadium helps to create alloys with the best strength-to

Terminology for Titanium Microstructures

AS1814F (Current)

07/16/2020

This list of terms, with accompanying photomicrographs where appropriate, is intended as a guide for use in the preparation of material specifications.

AMS G Titanium and Refractory Metals Committee

Spatially Optimized Diffusion Alloys: A Novel Multi-Layered Steel Material for Exhaust Applications

2020-01-105104/14/2020

A novel Spatially Optimized Diffusion Alloy (SODA) material has been developed and applied to exhaust systems, a very aggressive environment with high temperatures and loads, as well as excessive corrosion. Traditional stainless steels disperse chromium homogeneously throughout the material, with varying amounts ranging from 11% to 18% dependent upon its grade (e.g. 409, 436, 439, and 441). SODA steels, however, offer layered concentrations of chromium, enabling an increased amount along the outer surface for much needed corrosion resistance and aesthetics. This outer layer, approximately 70µm thick, exceeds 20% of chromium concentration locally, but is only 3% in bulk, offering selective placement of the chromium to minimize its overall usage. And, since this layer is metallurgically bonded, it cannot delaminate or separate from its core, enabling durable protection throughout manufacturing processes and full useful life. The core material may be of various grades, however, so this

Kotrba, Adam, Quan, Tony, Wei, Winston, Detweiler, Zachary, Keifer, David, Bullard, Daniel

Steel, Bars, and Forgings 0.50Cr - 0.55Ni - 0.25Mo (0.38 - 0.43C) (SAE 8740) Heat Treated, 105 ksi (724 MPa) Tensile Strength

AMS6325L-TEST-REC (Historical)04/10/2020

This specification covers an aircraft-quality, low-alloy steel in the form of heat treated bars and forgings.

AMS E Carbon and Low Alloy Steels Committee

Steel, Bars, and Forgings 0.50Cr - 0.55Ni - 0.25Mo (0.38 - 0.43C) (SAE 8740) Heat Treated, 105 ksi (724 MPa) Tensile Strength

AMS6325L (Current)

04/10/2020

This specification covers an aircraft-quality, low-alloy steel in the form of heat treated bars and forgings.

AMS E Carbon and Low Alloy Steels Committee

Titanium Alloy, Round Bar and Wire 3Al - 8V - 6Cr - 4Mo - 4Zr Consumable Electrode Melted Solution Heat Treated and Cold Drawn

AMS4957G (Current)01/14/2020

This specification covers a titanium alloy in the form of round bar and wire, 0.625 inch (15.88 mm) and under in nominal diameter or thickness.

AMS G Titanium and Refractory Metals Committee

Study on Effect of Laser Peening on Inconel 718 Produced by DMLS Technique *CSP Meta Testing 2*

2019-28-014610/11/2019

In Additive manufacturing, Direct Metal Laser Sintering (DMLS) is a rapid manufacturing technique used for manufacturing of functional component. Finely powered metal is melted by using high-energy fiber laser, by Island principle strategy that produces mechanically and thermally stable metallic component with reduced stresses, thermal gradients and at high precision. Inconel is an austenitic chromium nickel-based superalloy often used in the applications which require high strength and temperature resistant. It can retain its properties at high temperature. An attempt is made to examine the effect of laser shot peening (LSP) on DMLS Inconel 718 sample. Microstructure shows elliptical shaped structure and formation of new grain boundaries. The surface roughness of the material has been increased due to the effect of laser shock pulse and ablative nature. Macro hardness increased to 13% on the surface. Depth wise microhardness was investigated, found to be 17% increase on the sub-layer

Navin Kumar, Nattudurai, Yadav, Aditya Chandrakant, Raja, Kumar, Prabhakaran, Subramanian, Naiju, Chooriyaparambil Damodaran, Kalainathan, Sivaperuman

The Challenge of Replacing Hard Chrome

TBMG-3535910/01/2019

The Challenge of Replacing Hard Chrome

19AERP10_0310/01/2019

The search for a suitable replacement for hard chrome on aerospace components has been a key supply chain priority for aircraft manufacturers. This is because of the documented health risks to workers and the impact on the environment from exposure to hexavalent chromium, a carcinogen that occurs during the chrome plating process and is the most toxic form of chromium. As a result, chromium is a highly regulated chemical in major markets worldwide. In the European Union, hexavalent chromium falls under the domain of the EU regulation, REACH (Registration, Evaluation, Authorization and Restriction of Chemicals), which establishes guidelines for the safe use of chemicals throughout the supply chain. Chromium is also closely regulated in the United States by OSHA.

Aluminum Alloy, Sheet and Plate, Alclad 4.4Cu - 1.5Mg - 0.60Mn (2024, -T3 Sheet/-T351 Plate with 1-1/2% Alclad) Solution Heat Treated, Cold Worked and Naturally Aged

AMS4041T (Current)09/03/2019

This specification covers an aluminum alloy in the form of sheet and plate alclad two sides, over 0.187 to 1.000 inch (over 4.750 to 25.40 mm) in nominal thickness, supplied in the -T3/-T351 temper.

AMS D Nonferrous Alloys Committee

Calculation of Electron Vacancy Number in Superalloys

AS5491D (Current)

07/24/2019

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

Inspection of Ground, Chromium Plated Steel Parts

AMS2440C (Current)07/18/2019

This specification covers the requirements for inspection of ground chromium plated surfaces for grinder-induced damage to the chromium plate and substructure. The specification also provides users with criteria for distinguishing between such damage and acceptable indications inherent to the chromium plate.

AMS B Finishes Processes and Fluids Committee

Chemical Check Analysis Limits Titanium and Titanium Alloys

AMS2249J (Current)

04/05/2019

This specification defines limits of variation for determining acceptability of the composition of cast or wrought titanium and titanium alloy parts and material acquired from a producer.

AMS G Titanium and Refractory Metals Committee

Steel Bars, Forgings, and Tubing 0.50Cr - 0.55Ni - 0.20Mo (0.15 - 0.20C) (SAE 8617)

AMS6272N (Current)

08/02/2018

This specification covers an aircraft-quality, low-alloy steel in the form of bars, forgings, mechanical tubing, and forging stock.

AMS E Carbon and Low Alloy Steels Committee

Aluminum Alloy, Sheet and Plate, Alclad 4.4Cu - 1.5Mg - 0.60Mn (2024, -T3 Sheet/-T351 Plate with 1½% Alclad) Solution Heat Treated, Cold Worked and Naturally Aged

AMS4041S (Historical)04/03/2018

This specification covers an aluminum alloy in the form of sheet and plate alclad two sides, over 0.187 to 1.000 inch (over 4.750 to 25.40 mm) in nominal thickness, supplied in the -T3/-T351 temper.

AMS D Nonferrous Alloys Committee

Special Purpose Alloys ("Superalloys")

J467B_201802 (Current)02/15/2018

The data given in Tables 1–4 are typical values only and are not intended for design parameters. Mechanical properties of the special purpose alloys depend greatly upon processing variables and heat treatment. It is recommended that design data be obtained by actual testing or by consultation with the producers of the alloys.

Metals Technical Committee

Aluminum Alloy, Sheet and Plate, Alclad 4.4Cu - 1.5Mg - 0.60Mn (2024-O with 1 ½% Alclad); Annealed

AMS4040P (Current)02/15/2018

This specification covers an aluminum alloy in the form of sheet and plate, alclad two sides, 0.188 to 1.750 inch (4.775 to 44.450 mm) inclusive, in thickness, supplied in the annealed (O) condition (see 8.5).

AMS D Nonferrous Alloys Committee

Chemical Compositions of SAE Wrought Stainless Steels

J405_201801 (Current)

01/09/2018

The chemical composition of standard types of wrought stainless steels are listed in ASTM Specification A240. The UNS 20000 series designates nickel-chromium manganese, corrosion resistant types that are nonhardenable by thermal treatment. The UNS 30000 series are nickel-chromium, corrosion resistant steels, nonhardenable by thermal treatment. The UNS 40000 however, includes both a hardenable, martensitic chromium steel and nonhardenable, ferritic, chromium steel. Reference to SAE J412 is suggested for general information and usage of these types of materials. See Table 1.

Metals Technical Committee

Zinc Alloy Ingot and Die Casting Compositions

J468_201801 (Current)

01/09/2018

SIMILAR SPECIFICATIONS—UNS Z33521, former SAE 903, ingot is similar to ASTM B 240-79, Alloy AG40A; and UNS Z33520, former SAE 903, die casting is similar to ASTM B 86-76, Alloy AG40A. UNS Z35530, former SAE 925, ingot is similar to ASTM B 240-79, Alloy AC41A; and UNS Z35531, former SAE 925, die casting is similar to ASTM B 86-82a, Alloy AC41A.

Metals Technical Committee

Tool and Die Steels

J438_201801 (Current)

01/09/2018

This standard covers the identification, classification, and chemical composition of tool and die steels for use by engineers, metallurgists, tool designers, tool room supervisors, heat treaters, and tool makers.

Metals Technical Committee