This Sourcebook provides more than 150 data sheets selected from 700+ on stainless steels published in Alloy Digest over the past 40 years. Each two-page data sheet provides facts and figures about composition, physical and mechanical properties, heat treatment, machinability, workability, and castability (for casting alloys). Many graphs and tables are included. In addition, the Sourcebook features an in-depth introduction to stainless steels in general, including property comparisons and selection factors, and introductions to each family of alloys, covering general properties and applications, corrosion behavior, and fabrication characteristics.
Alloy Digest Sourcebook Stainless Steels Pdf Download
This study presents the effect of modelling the microstructure of duplex stainless steels with different geometric shapes and sizes on the indentation test results. In this study, an indentation test is modelled on duplex stainless steel (DSS) sheets. The actual and simulated microstructures are modelled with finite element program. Actual microstructure is modelled on SEM image of microstructure. In simulated microstructures, the austenite phase is modelled with four different geometric shapes: circle, small square, big square and triangle. While the indentation depth is found to be 25.80 μm experimentally, an average depth of 22.58 μm is reached in the simulations. Also, the effect of microstructures of different phase ratios on indentation behaviour is investigated. When the austenite ratio increases by 13%, it is observed that the indentation depth increases by 2.1% on average. In summary, the actual and simulated microstructures in different shapes and sizes give similar deformation results.
Stainless steels are high-alloyed steels with a minimum chromium content of 10.5 wt%. Historically, stainless steels have been classified by microstructure and are described as austenitic, martensitic, ferritic, or duplex (austenitic-ferritic). In addition, a fifth family, the precipitation-hardenable (PH) stainless steels, is based on the type of heat treatment used rather than the microstructure [1]. The stainless steel families have different mechanical properties. The martensitic stainless steels have high strength, but low ductility, whereas the austenitic stainless steels have lower strength but much higher ductility. The ductility of ferritic and duplex stainless steels (DSSs) lies between those of martensitic and austenitic alloys, with ferritic stainless steels having similar strength levels to the austenitic alloys. The strength levels of the DSSs are higher than those of the austenitic alloys, but lower than those of the martensitic materials. DSSs have approximately 2 times higher yield strength than austenitic stainless steels due to their high nitrogen content in their chemical composition. Also, pitting and stress-corrosion cracking resistance of DSSs are equal or higher than austenitic stainless steel. On the other hand, DSSs have austenitic and ferritic phases at the same time in the same microstructure. Mostly the internal structures consist of 50% ferrite and 50% austenite. In summary, the DSSs carry good properties of both austenitic and ferritic stainless steels [2].
In order to perform a structural analysis with FEM program, the mechanical properties of the materials need to be known. In the ABAQUS program, the elasticity modulus of the material, true stress-true plastic strain values are needed for the structural analysis. For this reason, the tensile test was performed on the DSS and the relevant parameters were determined. Mechanical properties of the DSS were determined using ASTM-E8/E8M-15a tensile test standard [24]. Tensile tests were performed by an INSTRON tensile tester, which has a maximum 100 kN loading capacity, with monotonic loading at a cross head speed of 10 mm per min. The strain values were determined with a mechanical extensometer. Although the mechanical properties of DSS can be determined by tensile testing, the mechanical properties of austenitic and ferritic phases cannot be determined by tensile testing. Therefore, not only the DSS was tested by tensile test but also austenitic and ferritic stainless steels were tested for the modelling of ferrite and austenite phases. EN 1.4301 (AISI 304) and EN 1.4016 (AISI 430) stainless steel grades were used for tensile tests of austenitic and ferritic stainless steel, respectively. In the tensile test result, engineering strain and engineering strain curves were obtained. These curves were converted to true strain and true strain curves using Eqs. (1) and (2):
Stainless steels (SS) are alloys of iron and carbon which should contain at least 11% chromium [1]. Alloying elements besides chromium and nickel such as molybdenum, copper, and titanium, provides some advanced durability conditions [2]. SS product usage is distributed as in industries of chemical and power engineering (34%), food and packages (18%), and transportation (9%), followed by in household applications (28%) and electronic devices (6%) [3].
Annual production of stainless steel has been increasing since the first production of the alloy. Only recently world stainless-steel production decreased by 2.5% between 2019 and 2020 due to Covid-19. World stainless-steel melt shop production rebounded with an increase of 10.6% year on year in 2021 to 56.3 million mt, according to figures released by International Stainless Steel Forum (ISSF) on March 14 [4].
Emissions of CO2 from different stages of stainless-steel production are examined separately. Emission quantification is needed for mainly three steps. These are i) ore preparation, ii) ferroalloy production, and iii) stainless-steel production and conversion into a final product. While all these stages cause CO2 emissions at certain rates, emissions vary depending on the production method of the electrical energy used for production. Chromium and nickel are responsible for 34.9 and 23.8% of total CO2 emission of production, respectively. The stages that cause most of the CO2 emission in order to produce 1 ton of SS production can be listed as follows: 1.01 ton CO2 (34.9%) from chromium production, 0.69 ton CO2 (23.8%) for nickel production, 0.49 ton CO2 (17.0%) for electricity, and 0.44 ton CO2 (15.2%) for direct emissions [6].
As CO2 emissions in stainless-steel production are dominated by the preparation stages of Cr and Ni alloys, new methods should be investigated in order to decrease the usage of electricity or energy and CO2 emissions [7].
We are also not aware of any previous studies that have identified lead contamination of cookware available for purchase in the U.S. This poses a risk to all U.S. residents. We conclude that stainless steel is likely a safer alternative to aluminum, although it is important to determine whether any ancillary components are manufactured from lead-containing alloys, like brass.
The past several years have seen the continued research and development of suitable materials for arthroplasty. Current cervical TDR designs constitute a wide range of biomaterials available for their construction. The most common design used includes metallic endplates which are fixed to the vertebral bodies above and below, with one or more articulations that involve metal-on-metal or metal-on-polymer bearing surfaces at the central core [6]. A broad range of materials are used in the cervical spine and include polyethylene, cobalt-chrome (CoCr) alloys, stainless steel, titanium (Ti) alloys, polyurethanes, and Ti alloy-ceramic composites. The choice of biomaterials utilized in these prosthetic implants centers around their sufficient durability, biocompatibility, and resistance to mechanical loading during physiologic use [7].
Articular surfaces may use components made from polymers such as ultrahigh molecular weight polyethylene (UHMWPE). Metals also play a key role in implant design and creation. Metallic components have been utilized which may wear more slowly than UHMWPE and include stainless steel, titanium (Ti), and cobalt-chrome (CoCr) alloy.
The precipitation hardened stainless steels are widely used as a structural material in chemical plants and power plants due to the optimum combination of good mechanical properties and corrosion resistance. Uniform distribution of fine intermetallic phases or alloying elements such as niobium and copper provide good mechanical properties [1-3]. The stainless X5CrNiCuNb16-4 (17-4 PH) steel is a martensitic grade containing 4 wt % of Cu. After supersaturation at 1040C and cooling in air it is aged at temerature range for 480C to 620C. The martensite formed during cooling after solution heat treatment as well as coherent Cu-rich precipitates contribute to high strength of the 17-4PH steel. Low content of carbon (less than 0.07 wt. %) cause that the martensite formed after solution heat treatment is plate-like, ductile. It is due to a low extent of strengthening of the steel with the interstitial atoms of carbon and nitrogen. After solution heat treatment the yield strength of the 17-4PH steel is 750 MPa and increases further up to 1200 MPa after aging at 482C [4^6].
Chromium stainless steels including grade 17-4PH become brittle when the a' phase forms as a result of spinodal decomposition [9-15]. As the Cr concentration in 17-4PH steel is near spinodal curve, after the long-term aging at temperature below 450C, a spinodal decomposition of martensite into Fe-rich a phase and Cr-rich a' phase is likely to occur. Stainless 17-4PH steel exhibits a high suscebility to cracking as a result of aging at 400C. This is due to formation of a' phase [9^12]. This phase is observed also after aging at 482C [12]. Formation of a' phase in the microstructure is associated with a substantial drop of cracking resistance [11, 12].
Industrial production of chromium proceeds from chromite ore (mostly FeCr2O4) to produce ferrochromium, an iron-chromium alloy, by means of aluminothermic or silicothermic reactions. Ferrochromium is then used to produce alloys such as stainless steel. Pure chromium metal is produced by a different process: roasting and leaching of chromite to separate it from iron, followed by reduction with carbon and then aluminium. 2ff7e9595c
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