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An apparatus has been developed for the measurement of mutual miscibility temperatures of binary liquid mixtures coexisting with a high pressure gas to examine to what extent the phase behavior changes. Methanol + hydrocarbon (cyclohexane, hexane, octane, and decane) binary mixtures were selected as typical polar and non-polar mixtures. And their mutual miscibility temperatures were measured at temperatures from 275.4 to 363.9 K and pressures up to 2.2 MPa with pressurized carbon dioxide (CO2). The experimental results were correlated with the NRTL equation by adopting a pseudo-binary mixture treatment. The NRTL interaction parameters between methanol and hydrocarbons were assumed to vary due to the presence of CO2. A good agreement between the experimental and the correlated mutual miscibility temperatures is obtained.

An investigation was carried out of the factors influencing the toughness of flash welded high strength steel plate.1 It was explained that the major factors for toughness degradation can be summarised by the following: there is an inclusion factor, that is oxides which remain at the weld interface and act as the starting point for fracture and the inclusions within steel which tend to be parallel to the weld interface due to metal flow; there is a microstructural factor, that is degradation of the microstructure due to coarsening of former g grains, a localised softened layer at the weld zone centre and the texture formed where there has been heavy rolling. Consequently, in order to secure toughness, a reduction of oxides at the weld interface and an improvement of steel material purity are required for the former case and the post weld heat treatment is required for the latter.

(2004). Factors affecting flash weldability in high strength steel – a study on toughness improvement of flash welded joints in high strength steel. Welding International: Vol. 18, No. 6, pp. 436-443.

Summary This paper deals with the resistance spot weldability of steel to aluminium alloy using an intermediate layer of aluminium clad steel. Five types of clad sheet with various steel/aluminium thickness ratios were produced by hot rolling. The mechanical properties of the clad sheet changed with the thickness ratio and ranged between those of steel and:those of aluminium sheet. The peel strength of the steel/aluminium interfaces was greater than 25 N/mm. Materials used in spot welding were 0.8 mm thick EDDQ steel sheet, three types of 1.0 mm thick aluminium alloy sheet and the clad sheet mentioned above. Spot‐weldability, including suitable welding current, nugget diameter, tensile shear strength and thickness of the intermetallic compound layer formed at the interface of the clad sheets, changed with the thickness ratio of the clad sheet. From these results, it was concluded that spot‐weldability was affected by the thickness ratio of the clad sheets. Spot‐weldability was also affected by the alloyin...

Summary This paper describes an investigation of the effects of the chemical composition of the base material on the quality of flash welds. Bending tests of welds were run for 43 types of steel sheets, including solution‐strengthened, precipitation‐strengthened, and complex structure‐strengthened (dual‐phase) high‐strength steels up to 590 MPa. A fractographic analysis showed cracks at the weld interface to be caused by oxide inclusions. Aluminium, silicon, and manganese are the major constituents of the inclusions, and the relative intensity of effect of these elements broadly has an Al:Si:Mn = 10:1:0.01 sequence. Carbon is also shown to affect interface cracking by reducing weld ductility. An equivalent formula is experimentally established to determine the effects of these elements on interface cracking. The ordinary bending test is shown to be a simple and reliable method for quantitative evaluation of the interface quality of flash welds, with the notch bending test being more effective for evaluati...

Summary This paper describes an investigation of the resistance spot weldability of aluminium clad steel sheet to steel or aluminium sheet as well as joining of a steel to an aluminium sheet with an aluminium clad steel sheet as an intermediate layer. The clad steel sheet was produced by hot‐rolling of steel and aluminium sheet by a direct resistance heating process. The mechanical properties of the clad steel sheet were between those of the steel and aluminium sheet, and the peel strength was satisfactorily high. The materials used in spot welding were a 0.8 mm thick EDDQ steel sheet, a 1.0 mm thick aluminium‐magnesium alloy sheet, and a 0.8 mm thick clad steel sheet which had an aluminium/steel thickness ratio of 1.1:1. Spot welding of steel sheet to the steel side of the clad steel sheet and aluminium sheet to the aluminium side of the clad steel sheet was successful. Spot welding of steel sheet to aluminium sheet using the clad steel sheet as an intermediate layer was also successful. The spot welding...

(1992). Resistance spot weldability of coated sheet for automotive application. Welding International: Vol. 6, No. 9, pp. 695-699.

(1992). Thermal history simulation of mechanical properties of HAZs in gold wire bonding. Welding International: Vol. 6, No. 10, pp. 780-785.

Intraperitoneal injection of PLA into C57BL/6 mice induced high levels of macrophage-mediated cytostatic activity. Maximal cytostatic activity was found 3 days after injection of 100 mg/kg of PLA. In contrast, natural killer cell activity was not affected by PLA. Thus, PLA selectively modulates macrophage activity without influencing NK activity.