Analysis of geometry dependencies of bead shaping was carried out at full-scale modelling of technologically possible cross-sections of beads deposited on narrow substrate of 0.5-5.0 mm thickness. The tasks were specified for technological regulation of shape of single-layer bead and series of process criteria was stated, namely efficient rising of narrow substrate being deposited, optimum effective cross-section of the bead and acceptable side machining allowances. Proposed are the formulae for estimation engineering calculations determining the relationship between required height of deposited layer, bead size, mass of deposited metal and filler consumption. 16 Ref., 3 Tables, 9 Figures. K e y w o r d s : microplasma powder cladding, nickel heat-resistant alloy, narrow substrate, full-scale modelling of bead cross-section, process criteria of bead shape

The desire to minimize the nickel content of steels intended for service in cryogenic systems had led to research on the applicability of iron manganese alloys at 101-/ temperatures. In this paper the relevant physical metallurgy of the Fe-t'ln system is revie. .. •:ed and cryogenic alloy development. .

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Cored wires are used in numerous welding processes with or without external gas or flux shielding. Submerged arc welding (SAW) with cored wires, seamed or seamless, for joining mild and low alloyed steel grades is a technique that has demonstrated clear advantages during the three last decades. Ever since its invention, the SAW process has evolved with one main goal: to combine quality with productivity. With low alloy wires, the benefits have already been clearly demonstrated and widely exploited. However, little has been written on SAW and cladding with cored wires for corrosion or heat resisting applications. Its extension to high alloy compositions brings corresponding benefits and adds some specific and unique features. This paper focuses on consumable specificities and on the quality and productivity features of SAW with CRA (corrosion resistant alloy) cored wires. It describes the potential as well as the limitations of this technique. Cored wires are now used for submerged arc welding of almost all stainless steels ranging from soft martensitic to super-duplex, and for a series of nickel base compositions as well as for cladding cobalt base alloys. Examples of industrial applications with austenitic, duplex, martensitic and heat resisting stainless steels are given to illustrate the potential of the cored wire solution. 13 Ref., 4 Tables , 25 Figures.

Comparative investigation of hot cracking sensitivity of commercial welding wires has been performed. It is shown that an all-purpose method of weldability evaluation can be the machine method with controllable forced deformation during TIG welding (PVR-test method), which allows separating the conditions of initiation of solidification cracks and ductility dip cracks in the weld and HAZ metal, and provides comprehensive information about quantitative characteristics of cracking sensitivity. 6 Ref., 9 Figures. K e y w o r d s : weldability, hot cracks, crack resistance evaluation, high-alloyed steels, nickel alloys

When in a strain state, molybdenum alloy sheets exhibit distinct anisotropy of mechanical characteristics. The anisotropy of elastic, strength, and plastic characteristics is due to crystallographic and structural textures formed in the alloys in the course of rolling. The highest yield strength values, irrespective of the molybdenum alloy chemical composition, are noted in specimens cut transverse to the rolling direction. As to plasticity characteristics, no clear relationship is observed. For some alloys the maximum values of elongation are achieved in the specimens cut out in the rolling direction, while for the others an angle of 45°to the rolling direction. A tensorial criterion is put forward which allows description of the total curve of strength or elasticity characteristics in the plane of the sheet. The textural analysis has failed to give any positive results in describing the curve of yield-strength anisotropy but it can provide a fairly accurate description of the elastic modulus behavior.Strain anisotropy arises in molybdenum alloy sheets due to plastic deformation during forming (rolling) operations. The physico-mechanical characteristics governed by plastic deformation in the metal are not the same in various directions, i.e., they are anisotropic. This is attributable to a variation of the value of shear stresses that are active in variously oriented areas and responsible for an ambiguity of the extent of plastic deformation. In this case, the greatest distinction should be expected not between longitudinal and transverse (with respect to the rolling direction) stresses but between longitudinal and diagonal ones. Assessment of the degree of anisotropy in a material that experienced directional plastic deformation, e.g., in the process of rolling, from the standpoint of strength characteristics of specimens cut longitudinally in and transverse to the rolling direction is not only inadequate but also erroneous, for every so often significant differences in mechanical properties between intermediate directions are encountered.The present work addresses the in-plane anisotropy of mechanical characteristics of sheet molybdenum alloys whose chemical composition is given in Table 1 below.Sheets of the molybdenum alloys were made by multi-pass hot rolling at a temperature which was 100°C lower than the recrystallization temperature of these alloys. The final sheet thickness was 1.2 mm and the total strain upon rolling was 88%.Mechanical characteristics in uniaxial tension were measured on the specimens cut from a sheet at various angles to the rolling direction (RD). The specimens cut longitudinally (LD) and transverse to the rolling direction (TD) make respective angles 0°and 90°with the rolling direction. The cold-shortness temperature was assessed by the minimum temperature whereby all the specimens withstood 90°bending without breaking. 5660039-2316/05/3706-0566