Browse Topic: Chromium

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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
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 to phosphorus and sulfur because of the degree to which these elements segregate. Boron is not subject to product analysis tolerances.
Metals Technical Committee
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
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
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
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 of the material due to the effect of a hardened matrix formed by precipitation hardening and grain size refinement attributed by laser shock peening. SEM analysis shows larger grains are being refined into smaller grains. The residual stress analysis result shows compressive residual stress values have increased.
Navin Kumar, NattuduraiYadav, Aditya ChandrakantRaja, KumarPrabhakaran, SubramanianNaiju, Chooriyaparambil DamodaranKalainathan, Sivaperuman
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
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
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
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
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
Objective Method to Quantify Ecological Toxicity between Friction Materials2017-01-24959/17/2017
California and Washington recently passed legislation to limit certain constituents in brake pad friction materials. As part of the California (CA) legislation enacted in 2010, brake pad manufacturers need to perform an alternative assessment to identify potentially safer environmental and toxicological choices for future friction material production. Copper, chromium VI-salts, lead, cadmium, mercury, and other compounds have been identified as potentially unsafe to the environment. This paper contains the methodology behind an objective and comprehensive alternative assessment to quantify the ecological impact of friction materials. Utilizing raw material specific Chemical Abstracts Service (CAS) numbers and their associated toxicological reference values (TRVs), this newly defined method estimates the total toxicological impact of finished friction materials on both the environment and on a human carcinogenic level to allow the manufacturer to screen greener alternatives. Utilizing chemical specific TRVs such as the lethal concentration 50% (LC50), median effective concentration 50% (EC50), and the median effective reproductive concentration 50% (ErC50), this method quantifies ecological impact characteristics of brake pad friction material. In the same regard, the carcinogenic properties of each chemical are evaluated, placed into groupings based on their carcinogenic potential as evaluated by the International Agency for Research on Cancer (IARC) and are utilized to generate comparative carcinogenic ratings. The methodology is best utilized as a relative comparison between multiple uncompressed friction formulations in order to create greener friction material for the future.
Visser, Andrew M.Severnak, Scott
Starter Motor Light Weighting through Use of Alternate Materials2017-28-19677/10/2017
Global Automotive Industry is mandated with the task of emission reduction and mileage improvements. One of the key areas being looked at from mileage standpoint is light weighting. While Aluminum body is replacing Steel is many vehicular applications, in Starter Motor Aluminum is the key component. Therefore, any attempt at light weighting must consider Aluminum. A Starter motor fits directly on to the engine. Aluminum being the housing material provides structural stability. It also performs the role of heat dissipation being a good thermal conductor and source of electrical ground path. Aluminum constitutes 20 - 25% of Starter motor weight. Any significant weight reduction cannot be achieved unless we look at the components made of Aluminum, namely die cast Housing and End plate. The alternatives considered in this study include engineered plastics, magnesium alloy and composites. The prime reasons for evaluation of these materials include the ones listed above - structural stability and strength, electrical and thermal conductivity. Detailed study was carried out which included material characterization, FEA analysis, thermal studies and finally rigorous physical testing. The results present the comparison of all the various alternate materials. The ultimate deciding factor must include cost as these materials, while scoring over Aluminum in weight (density) cost a premium. The paper will also address the tradeoff - cost vs. benefit, for the car manufactures if they decide to choose the alternative.
Nagapillai Durairaj, Senthil RamGanesan, ThulasirajanChakrapani Rao, Praveen
This specification covers a blend of chromium carbide and a nickel-chromium alloy in the form of powder.
AMS F Corrosion Heat Resistant Alloys Committee
This standard describes general and detailed methods of sampling and testing for surface passivity of corrosion-resistant steel parts. These tests may also be useful to determine if there is a need for passivation.
AMS F Corrosion Heat Resistant Alloys Committee
A New Two Cylinder Diesel Engine Family for Off-road in Naturally Aspirated and Turbocharged Intercooled Versions2016-01-233510/17/2016
The design and development of a new four-stroke two-cylinder diesel engine family of 1.29 litre capacity for off road are discussed. The engine is in naturally aspirated and turbocharged and intercooled versions and rated from 11.9 kW/1500 rpm to 25.7 kW/2500 rpm. The engines were tuned for air and fuel flows, air utilisation, fuel air mixing, performance and emissions at steady state at a development lab and later certified in national labs. The high altitude capability of the TCIC was checked using a model. The engines rated at less than 19 kW satisfy India Generator set and off road norms of India and Europe equivalent to USTier4 standard, and at higher ratings, standard equivalent to US Tier4-interim. In the second part of the paper, the design of coolant and oil pumps, oil cooler for TCIC engine and the piston with steel oil control ring are discussed. The higher loaded TCIC engines use fillet hardened crankshafts of chromium molybdenum steel. The crankcase integrated with the flywheel housing and the timing case at the front, in conjunction with a cast iron sump makes the engine rigid against torsion and bending in an agricultural tractor. The firing order 0°-360° with the two pistons moving in phase allows lower cyclic irregularity and a light flywheel as well as turbocharging. The resultant primary reciprocating inertia force is neutralized by a counter-rotating balancer shaft and the fluctuations in crankcase pressure are taken care by a valve in the breather to avoid oil carry over.
Lakshminarayanan, P. A.Senthilkumar, P. K.
This specification covers high-strength, low-alloy steels in the form of sheet and plate up to 4.000 in. (101.60 mm) in nominal thickness.
AMS E Carbon and Low Alloy Steels Committee
Tribological Properties of Engine Lubricant With Nano-Copper Oxide as an Additive2016-01-04874/5/2016
Anti-wear additives are mostly required to improve lubricant properties and hence tribological performance. Addition of nanoparticles to lubricant oils reduces friction and thus enhances the lubrication characteristics. The mechanism of friction reduction in friction could be justified by more than one method. In this work, copper oxide nano-material was added to the engine lubricant oil Mobil 1 SAE15W-40SF with 0.1% wt. concentration. Two new engines were used and operated for 1000 hours, where nanolubricant was added to one of them and regular lubricant was used in the other. Twelve samples were taken periodically from each engine. ASTM-D6595 spectrometry standard was used in order to measure the wear particles in the taken oil samples. Further investigation was done by doing more tests to some of the oil samples using Laser Net Fines Analyzer. Results showed an improvement in the friction properties through a reduction in wear rates in the case of using nano-additives. Basically a wear reduction is found for aluminum, iron and chromium wear particles by 48%, 11.5% and 42%, respectively. Also, an average reduction in amount of specific wear particle was found by 39%, 36% and 60% for cutting wear, severe sliding wear and fatigue wear, respectively. A relevant decrease in engine temperature is found as well.
Akl, Sayed Y.Abdel-Rehim, Ahmed A.Khafagy, Esraa A.
Development of Trivalent Chromium Passivation for Zn Platng with High Corrosion Resistance after Heating2016-01-05424/5/2016
Trivalent chromium passivation is used after zinc plating for enhancing corrosion resistance of parts. In the passivating process, the amount of dissolved metal ions (for example zinc and iron) in the passivation solution increases the longer the solution is used. This results in a reduced corrosion resistance at elevated temperatures. Adding a top coat after this process improves the corrosion resistance but has an increased cost. To combat this, we strove to clarify the mechanism of decreased corrosion resistance and to develop a trivalent chromium passivation with a higher corrosion resistance at elevated temperatures. At first, we found that in parts produced from an older solution, the passivation layer has cracks which are not seen in parts from a fresh/new solution. These cracks grow when heated at temperatures over 120 degrees Celsius. Next we researched the reason for cracks to occur and found that the main difference between an old and new solution’s layer is the amount metal deposits in it. These metal ions deposit into the passivation as hydroxides, and the larger the quantity in this layer the more the layer contracts by heating, meaning the newer the solution the less the layer contracts. So, we investigated developing a new solution to improve the corrosion resistance after heating through the reduction of metal ion deposits in the passivation layer. We achieved this reduction by adding organic carboxylic acid to chelate the dissolved metal ions. The carboxylic acid prevents excess depositing of these ions in the passivation layer. Using this developed solution, cracks disappeared and the corrosion resistance after heating was improved.
Kawaguchi, HiroshiFunatsumaru, OsamuSugawara, HiroyoshiSumiya, HiroshiIwade, TakanobuYamamoto, TomitakaKoike, TakashiKashio, Ryuta
This document, as referenced in the applicable product specifications in procurement documents, contains: a A catalog of the standard carbon steels, alloy steels (including H-steels), and stainless and heat-resisting steels that are designated by chemical composition, or (for H-steels) by chemical composition and hardenability limits by reference to standard industry documents. b Rules for designating the chemical content of carbon steels, alloy steels, and stainless and heat-resisting steels that are not classified as standard.
AMS E Carbon and Low Alloy Steels Committee
Chemical Compositions of SAE Carbon SteelsJ403_201406 (Historical)6/30/2014
In 1941, the SAE Iron and Steel Division, in collaboration with the American Iron and Steel Institute (AISI), made a major change in the method of expressing composition ranges for the SAE steels. The plan, as now applied, is based in general on narrower cast or heat analysis ranges plus certain product analysis allowances on individual samples, in place of the fixed ranges and limits without tolerances formerly provided for carbon and other elements in SAE steels. For years the variety of chemical compositions of steel has been a matter of concern in the steel industry. It was recognized that production of fewer grades of steel could result in improved deliveries and provide a better opportunity to achieve advances in technology, manufacturing practices, and quality, and thus develop more fully the possibilities of application inherent in those grades. Comprehensive and impartial studies were directed toward determining which of the many grades being specified were the ones in most common demand, and the feasibility of combining compositions having like requirements. From these studies, the most common grades of steel have been selected and kept in the current revision. The cast or heat chemical composition limits or ranges of these grades are given in Tables 1, 2, 3A, and 3B. These cast or heat limits or ranges are subject to standard variations for product analysis as given in SAE J409. Since AISI is no longer issuing steel grade designations, grades listed in this document are SAE grades. It is recognized that chemical compositions other than those listed in the previously mentioned tables will at times be needed for specialized applications or processing. When such a steel is required, the elements comprising the desired chemical composition are specified in one of three ways: (a) by a minimum limit, (b) by a maximum limit, or (c) by minimum and maximum limits, termed a range. Standard cast or heat analysis limits and ranges for the various elements of carbon steels are given in Table 4. In this table, range is the arithmetical difference between the minimum and maximum limits (that is, 0.19 to 0.25 is a 0.06 range). These cast or heat limits and ranges are also subject to standard variations for product analysis as given in SAE J409. ISTC Division 1 has developed a procedure which allows for the maintenance of the grade lists in this document. This will involve conducting an industry-wide survey to solicit input. This survey will be conducted at a frequency deemed necessary by the technical committee. Criteria have been established for the addition to or the deletion of grades from the grade lists. New grades will be considered based on the grade meeting a SAE grade designation and chemistry, having a minimum production or consumption of 225 tonnes/year (250 tons/year) and has the sponsorship of at least two individual users or producers. New steel compositions will be considered as Potential Standard (PS) steels, based on the guidelines in SAE J1081, until such time as production of the new steel achieves a level of production or usage qualifying it for consideration as a standard steel. Deletion of grades will be by consensus based on the grade survey. Deleted grades will be archived in SAE J1249. When the cast or heat analysis is requested to be reported to demonstrate conformance to the chemical limits shown in Tables 1, 2, 3A, or 3B, in addition to the quantities of carbon, manganese, phosphorus, and sulfur, the following elements and their quantities shall also be reported: copper, chromium, nickel, molybdenum, and silicon. When the amount of any one of these last five elements is less than 0.02% that analysis may be reported as “<0.02%.” Based on a survey question in the 2006 Grade Survey, the grade lists have been revised such that chemistries of all product forms are now consolidated into single tables. The chemistry ranges listed will be the narrowest range for the various product forms with the exception of S content. It is acknowledged however that due to differences in the section size of the various product forms, chemical composition demands for the product forms should be different to allow for adequate flexibility of steel application. These differences are reflected in Tables 4 and 5.
Metals Technical Committee
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