Stainless steel classifications

There are three general classification systems used to identify stainless steels. The first relates to metallurgical structure and places a particular stainless steel into a family of stainless steels. The other two, namely, the AlSl 

AISI Type UNS Designation AISI Type UNS Designation 

Numbering System and the Unified Numbering System (UNS) that were developed by ASTM and SAE to apply to all commercial metals and alloys, define specific alloy compositions. Table 5.1 through Table 5.3 provide a comparison between ASI and UNS designation for stainless steels. 

The various stainless steel alloys can be divided into seven basic families  

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Stainless steel classifications are based on material properties, method of fabrication and use of the end product. There are various societies, institutes, and so on, that classify stainless steel according to their own concerns and uses. You will most frequently run across the classifications from the American Iron And Steel Institute (AISI) and the American Society For Testing And Materials (ASTM). 

When a block is inside, the entrance panel is closed and the inspection is ready to start. The inside of the stainless steel X-ray tubehead housing is clad in lead with an on/ofT shutter in front of a thin plastic X-ray window. The thin window is to ensure the IP 65 classification. The window is of plastic that is not affected by the cleaning agents. The on/off shutter is interlocked with the entrance and exit panels so X-rays can be kept on at all times without risk of radiation leakage or exposure of the frozen fish blocks prior to the actual inspection. 

Production and Shipment. Estimated adiponitrile production capacities in the U.S. in 1992 were about 625 thousand metric tons and worldwide capacity was in excess of lO metric tons. The DOT/IMO classification for adiponitrile is class 6.1 hazard, UN No. 2205. It requires a POISON label on all containers and is in packing group III. Approved materials of constmction for shipping, storage, and associated transportation equipment are carbon steel and type 316 stainless steel. Either centrifugal or positive displacement pumps may be used. Carbon dioxide or chemical-foam fire extinguishers should be used. There are no specifications for commercial adiponitrile. The typical composition is 99.5 wt % adiponitrile. Impurities that may be present depend on the method of manufacture, and thus, vary depending on the source. 

Units are available in stainless steel or protected mild steel, often prefabricated, up to 12.5 m in diameter, capable of processing >5 m /s depending on the separation efficiency required. When the separator is used for classification of granular soflds, smaller-diameter (<4 m) units are used, separating nearly all particles coarser than - 150 fim. 

The uses of steel are too diverse to be Hsted completely or to serve as a basis of classification. Inasmuch as grades of steel are produced by more than one process, classification by method of manufacture is not advantageous. The most useful classification is by chemical composition into the large groups of carbon steels, alloy steels, and stainless steels. Within these groups are many subdivisions based on chemical composition, physical or mechanical properties, or uses. 

Classify the following as element, compound, or mixture, and justify your classifications salt, stainless steel, tap water, sugar, vanilla extract, butter, maple syrup, aluminum, ice, milk, cherry-flavored cough drops. 

Salt, sodium chloride classification compound. Stainless steel, mix of iron and carbon classification mixture. Tap water, dihydrogen oxide plus impurities classification mixture. Sugar, chemical name sucrose classification compound. Vanilla extract, natural product classification mixture. Butter, natural product classification mixture. Maple syrup, natural product classification mixture. Aluminum, metal classification in pure form—element (sold commercially as a mixture of mostly aluminum with trace metals, such as magnesium). Ice, dihydrogen oxide classification in pure form—compound when made from impure tap water—mixture. Milk, natural product classification mixture. Cherry-flavored cough drops, pharmaceutical classification mixture. 

The corrosivity of soils also depends upon the oxidation-reduction potential as classified by Booth et al.15 The classification scheme of the corrosivity of soils is given in Table 4.4b. Macrogalvanic cells are formed in underground pipelines due to foreign structure the combination of new and old pipe dissimilar metals (stainless steel and carbon steel) differential aeration dissimilar soils and stray currents. All these lead to localized corrosion of underground pipelines. 

Classification of stainless steels by alloy content and microstructure... 

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