Stainless steels cold work

With cold worked stainless steel, yield and ultimate stresses will depend upon work hardening. Assume that the material test for this steel gives ... 

H. Hanninen, U. Ehmsten, and J. Talonen, Environmentally-assisted cracking of cold worked stainless steels—A mechanistic point of view, in Proceedings of Work Shop on Cold Work in Iron and Nickel-Base Alloys Exposed to High Temperature Water Environments, Sponsored by CANDU Owners Group, AECL and EPRT, Toronto, Ontario, Canada, June 3-8,2007. 

The swelling of nonfissile materials in fast neutron fluxes has only recently been discovered (76). In spite of this its importance has already stimulated much work. Theories have been advanced for the nucleation and growth of voids under the vacancy supersaturation produced by the radiation field (77-79). Experimental data is available from EBR-II components for cold-worked and solution treated 304 and 316 stainless steels (80, 81) and from irradiations in DFR for a range of potential clad alloys (82, 83). Claudson has fitted EBR-II data to empirical relations, e.g., the swelling for 20% cold-worked stainless steel is given by (81)... 

Mosedale et al. were the first to publish useful fast flux irradiation creep data on cladding materials (86). They showed that the irradiation creep rate in solution treated 316 stainless steel is approximately proportional to stress and neutron flux at temperatures of about 250°C. Theoretical studies have predicted a creep rate stress dependence of a power less than 2 and a negative temperature dependence, i.e., at lower temperatures a faster creep rate (77). Claudson has observed such behavior with temperature and has suggested that a creep rate proportional to exp(—0.0027T), where T is in kelvins, should fit both solution treated and cold worked stainless steels. 

Sheet, thin plate, welded tubing, and small-diameter bar of commercially pure titanium are manufactured into parts by conventional cold-working techniques. The formability of titanium, when worked at room temperature, is like that of cold-rolled stainless steel. At 65°C the formability compares with stainless steel annealed at room temperature. Cold-working maybe difficult for some titanium alloys and heat may be required, especially for severe forming operations. Generally, titanium and its alloys are worked between 200 and 300°C. Lubricants reduce friction and galling. Slow forming speeds at controlled rates improve workability and are recommended for more difficult operations. 

Many initiators attack steels of the AISI 4300 series and the barrels of the intensifiers, which are usually of compound constmction to resist fatigue, have an inner liner of AISI 410 or austenitic stainless steel. The associated small bore pipework and fittings used to transfer the initiator to the sparger are usually made of cold worked austenitic stainless steel. The required pumping capacity varies considerably from one process to another, but an initiator flow rate 0.5 L / min is more than sufficient to supply a single injection point in a reactor nominally rated for 40 t/d of polyethylene. 

Zirconium is a hard, shiny, ductile metal, similar to stainless steel in appearance. It can be hot-worked to form slabs, rods, and rounds from arc-melted ingot. Further cold-working of zirconium with intermediate annealings produces sheet, foil, bar wire, and tubing. Physical properties are given in Table 3. 

The body-centered-cuhic (bcc) metals and alloys are normally classified as undesirable for low temperature construction. This class includes Fe, the martensitic steels (low carbon and the 400-series stainless steels). Mo, and Nb. If not brittle at room temperature, these materials exhibit a ductile-to-brittle transition at low temperatures. Cold working of some steels, in particular, can induce the austenite-to-martensite transition. 

Spiral-plate exchangers are fabricated from any material that can be cold worked and welded. Materials commonly used include carbo steel, stainless steel, nickel and nickel alloys, titanium, Hastelloys, and copper alloys. Baked phenolic-resin coatings are sometimes applied. Electrodes can also be wound into the assembly to anodically protect surfaces against corrosion. 

Levin, LA. and Maksimova, G. F., Effect of Cold Work on the Tendency Towards Intergranular Corrosion of Type 18-8 Stainless Steel, Khim Mashinosiroenie, 5, 35 (1%1) C.A., 56, 3219... 

Table 2.25 Breakdown potentials for 316S12 stainless steel (cold worked), high nitrogen stainless steel (cold worked), titanium-6Al-4V and cast-cobalt-chromium-molybdenum alloy in continuously aerated aqueous acidified chloride solution 0.23 m [C1 ] pH 1.5 at 25°C. ...

SI2 Stainless steel BS7252/1 Comp. D cold worked 180 -100... 

High nitrogen stainless steel BS7252/9 cold worked 850 300... 

Niobium is always found in nature associated with tantalum and it closely resembles tantalum in its chemical and mechanical properties. It is a soft ductile metal which, like tantalum, work hardens more slowly than most metals. It will in fact absorb over 90% cold work before annealing becomes necessary, and it is easily formed at room temperature. In addition, welds of high quality can be produced in the metal. In appearance the metal is somewhat similar to stainless steel it has a density slightly higher than stainless steel and a thermal conductivity similar to 1% carbon steel. 

Fig. 8.33 Effect of cold work (%) on the susceptibility to cracking of type 321 stainless steel in boiling magnesium chloride and calcium chloride solutions (after Sedriks )...

A 312 Seamless, Welded, and Heavily Cold Worked Austenitic Stainless Steel Pipes [Note (2)]... 

V. Kain, K. Chandra, K.. N. Adhe, P.K. De, Effect of Cold Work on Low-Temperature Sensitization Behavior of Austenitic Stainless Steels , Journal of Nuclear Materials, 334 (2004), 115-132. 

HN03 to the bomb, place the crucible in the electrode support of the bomb, and attach the fuse wire. Assemble the bomb and add oxygen to a pressure of 24 atm (gage). Place the bomb in the calorimeter (a cold water bath in a large stainless steel beaker is also satisfactory) and ignite the sample using appropriate safety precautions ordinarily employed in bomb calorimetry work. 

Trap desorption. The choice of the thermal desorption apparatus is critical in order to avoid contamination and to be able to work with aroma compounds in a wide range of retention indices. In all systems, problems can be encountered due to reactive compounds or cold spots within the analyzer. It is recommended that all transfer lines, valves, or surfaces in contact with the volatile compounds be made of an inert material such as fused-silica or deactivated glass-lined stainless steel. Even more ideal are systems that do not have long... 

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