Liquid heat treatment

Some liquid metals have been observed to cause embrittlement in many titanium alloys. In mercury, for example, Ti-8Al-lMo-lV exhibits both intergranular and transgranular fracture with velocities as high as lOcm/s. Heat treatment affects this behaviour in a manner similar to that observed in aqueous and methanolic solutions. Some alloys are embrittled by liquid cadmium and zinc. More surprising, perhaps, is the observed solid metal embrittlement which has been found on titanium alloy components coated with cadmium, silver or zinc Service failures of cadmium-plated Ti-6A1-4V fasteners have been reported , and cracking of this alloy and... 

Glass-ceramics are a family of materials that are polycrystalline in nature and are formed from the liquid or glassy state. A glass-ceramic article is made by the heat treatment of a vitreous body in two stages ... 

Solid Solid Solid-liquid Sludge, wet solid Asbestos insulation heat treatment salts, pulverized fuel ash refuse Filter cake Sewage sludge... 

Equipment should be supported in such a way that it will not rest in pools of liquid or on damp insulating material. Porous insulation should be weatherproofed or otherwise protected from moisture and spills to avoid contact of the wet material with the equipment. Specifications should be sufficiently comprehensive to ensure that the desired composition or type of material will be used and the right condition of heat treatment and surface finish will be provided. Inspection during fabrication and prior to acceptance is desirable. 

Electrodes of 2 x 2 cm2 geometric area were used in the experiments. In the case of platinum, a pretreatment by fast triangular potential scans (200-300 V/s between 0.05 V and 1.5 V RHE) followed by heating up to 900 K in a 3 x 10 6 mbar 02 atmosphere was carried out. Electrodes, pre-treated in this way, can be emersed with a thin liquid film, which can easily be evaporated in the vacuum chamber. The heat treatment drastically reduces contamination of the platinum electrode by carbon. The roughness factor is usually in the order of three. 

To reduce further the pore size and/or to introduce specific interactions between the solid surface and the liquid or gaseous medium in the pores, sol-gel layers need to be modified. In principle this is done by precipitation or by adsorption of components from a gaseous or liquid medium followed by heat treatment of the formed products inside the pores or the pore entrance. This will be further discussed in Section 2.7. 

Accessible surfaces of welds shall be inspected by magnetic particle or liquid penetrant examination after back chipping or gouging and again after postweld heat treatment or, for austenitic stainless steels, after solution annealing. 

A similar experiment was performed on the crystals grown by the method of liquid phase epitaxy (LPE) as the starting crystal. The starting crystals were reheated under various pressures of As gas at 850 °C for 30 min. Figure 3.38 shows the hole concentration, p, dependence on Pas at the surface of the heat-treated crystals. (The starting crystals showed n-type conduction, and after heat-treatment under this condition, only 7 pm of the surface of... 

Pitches can be transformed to a mesophase state by further chemical and physical operations. Heat treatment of conventional pitches results in additional aromatic polymerization and the distillation of low molecular weight components. This results in an increase in size and concentration of large planar aromatic molecular species whereupon the precursor pitch is transformed to a mesophase state exhibiting the characteristics of nematic liquid crystals (1). Additional heat treatment converts the mesophase pitch to an infusible aromatic hydrocarbon polymer designated as coke. 

Products were recovered by batch elution, using a variety of salt solutions for eluents and a large liquid-to-zeolite phase ratio (within the range 10 to 200). In a few cases, the exchanged zeolites were eluted without prior heat treatment to determine the behavior of the metal before it was fixed in the small pore structure. In most cases, the zeolite was ignited at 500-700°C to fix the metal before subsequent manipulations, including irradiation. 

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