Heat treated zone

AU other carbon steel, low-intermediate, and high-aUoy steels, ferritic steels Base metal Deposited weld metal and heat-affected zone (See Note 1) 2. Except when conchtions conform to Note 2, the material shall be heat-treated to control its microstructure by a method appropriate to the material as outlined in the specification applicable to the product form and then impact-tested. (See Note 1.) Deposited weld metal and heat-affected zone shall be impact-tested. 

Fig. 12.23 shows the variation of hardness with distance from surface for a chromised high-carbon steel (1% C). The full line represents the material as treated , the broken line corresponds to conditions after full-hardening and tempering. The apparent greater depth of the hard zone in the heat-treated material is due to the effect of small concentrations of chromium... 

H. Effluent exchanger channel welds, plate, and heat-affected zone, isolated areas damaged postweld heat treated at 1100°F. 

The austenitic stainless steels do not require PWHT as a hardness control measure. They are sometimes stress relieved or postweld heat treated to reduce residual stresses, thereby improving their resistance to stress corrosion cracking. The austenitic stainless steels are sometimes chosen in preference to the Cr-Mo low-alloy steels because PWHT can be avoided (the fusion zones of welds of the Cr-Mo low-alloy steels may be air hardenable). 

Fig. 7.8. Fligh-resolution images along the [001] zone of specimens which were heat-treated (a) cell-tripled superstructure (b) and (c) superstructures with four- and five-fold a-parameters.

At a continuous roller hearth type annealing furnace 24 pairs of regenerative radiant tube burners were applied to the heating and soaking zone shown in Figure 24.22. The material to be heat treated is cast iron joints and design net capacity of the furnace is... 

True electroosmotic flow has been demonstrated in horizontally mounted layers at modest field strengths (< 1 kV / cm) with mobile phases of high dielectric constant. Still unclear is which solvents can be used, the need for prewetted layers and ions as current carriers, the effect of local heating on zone profiles, and the effect of binder chemistry on flow, mass transfer, and thermal effects. Compared with capillary flow faster separations have been demonstrated, but the influence of flow velocity on efficiency was only treated in a qualitative sense. So far no comprehensive analysis of the kinetic properties of separations under conditions of electroosmotic flow have been performed in thin-... 

C (375 °F) for 4 h, and 6013-T6 (Ref 71). The hardness decrease compared to the parent-metal hardness, that is, the minimum hardness in the HAZs, following FSW is approximately 17% for the T4 temper, 29% following the 190 °C for 4 h postweld heat treatment, and 21% for the T6 temper (Ref 71). In addition, the results by Heinz and Skrotzki illustrate hardness as a function of through thickness. As expected, the weld zone is considerably softer than the base metal for all three heat treat conditions, with the soft zone on the surface extending 10 mm (0.4 in.) on both sides of the weld on the crown surface and approximately 6 mm away from the weld centerline near the root surface. This result illustrates the anisotropy in through-thickness hardness (and other properties) that can occur as a result of FSW. 

Fig. 7.23 Optical micrographs of (a) heat treated base metal (Ti-15-3) and (b) stir zone of postweld heat treated sample for friction stir welding on Ti-15-3...

Recio, 1., and Olieman, C., Determination of denatured serum proteins in the casein fraction of heat-treated milk by capillary zone electrophoresis. Electrophoresis, 17, 1228, 1996. 

Fig. 1.5. Continuous belt-conveyor type heat treat furnace (1800 F, 982 C maximum). Except for very short lengths with very lightweight loads, a belt needs underside supports that are nonabrasive and heat resistant—in this case, thirteen rows, five wide of vertical 4 in. (100 mm) Series 304 stainless-steel capped pipes, between the burners of zones 2 and 4. An unfired cooling one Is to the right of zone 3.

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