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In this study, fine position samples of heat affected zone under single and secondary thermal cycles were simulated by heat treatment method. The influence of secondary thermal cycle on softening behavior and mechanism of heat affected zone in TIG-welded spray formed 7055 aluminum alloy were studied. The results showed that the mechanical properties of the solid solution zone decreased after the second thermal cycle. The hardness of the solid solution zone decreased from 180HV to 103HV and the tensile strength decreased from 570 MPa to 346 MPa after the second thermal cycle. The main reasons for the reduction of mechanical properties in the solid solution zone after the second thermal cycle were the weakening of the solid solution strengthening effect and the occurrence of over-aging. After the second thermal cycle in the over-aging zone, the mechanical properties decreased and then increased with the increase of the thermal cycle temperature. The lowest hardness value in the over-aging zone after the second thermal cycle decreased from 124HV to 103HV, and the tensile strength decreased from 410 MPa to 284 MPa. The main reason for the decrease of mechanical properties in the overaging zone after the secondary thermal cycle was the intensification of overaging caused by the coarsening of η phase. Overall, the width of the heat affected zone increased after the secondary thermal cycle, and the most seriously softened area extended toward the fusion line.

Physical activity/exercise is one of the most important methods for cancer prevention, treatment and control in people of all ages and levels of physical activity. In the past 10 years, exercise oncology has been developing rapidly, and a large number of research results have proved that physical activity/exercise has a clear role in cancer prevention, enhancement of treatment effect, alleviation of toxic and side effects of treatment, as well as delaying metastasis and prolonging lifespan of patients. Physical activities recommended by WHO can effectively prevent common cancers. Most cancer survivors can follow WHO recommend to do exercise. However, given the complexity of cancer and its impact on the human body, it is safer and more effective for most cancer survivors to exercise according to exercise prescriptions. The importance of physical activity/exercise for cancer prevention and treatment should be fully understood by Oncology professionals and cancer patients, and efforts should be made to include exercise prescription as a standard part of the cancer prevention and treatment paradigm so that more patients can benefit from it. [ABSTRACT FROM AUTHOR]

In this study, the Al–KBF4–K2TiF6–Y in situ reaction system was used to prepare rare earth (RE) element Y-modified TiB2ceramic particles reinforced 7055 aluminum alloy welding consumables for inert gas shielded welding of spray-formed 7055 aluminum alloy. Compared with 0 Y- weld metal (WM), the grain size of the 0.1 Y-WM was refined from 30 μm to 25 μm. In the as-welded state, the tensile strength and elongation of 0 Y-7xxx and 0.1 Y-7xxx joints were 295 ± 6 MPa and 4.92 ± 0.24%, 327 ± 5 MPa and 6.45 ± 0.25%, respectively. The tensile strength and elongation of 0 Y-7xxx and 0.1 Y-7xxx joints after T6 heat treatment were 521 ± 5 MPa and 3.47 ± 0.24%, 557 ± 6 MPa and 4.84 ± 0.25%, respectively. The elongation of the 0.1Y-7xxx joint is 55.47% higher than that of the 0 Y-7xxx joint. The introduction of rare earth elements Y can improve the wettability of TiB2particles and the substrate so that TiB2particles are uniformly dispersed, and at the same time make TiB2particles edge blunting, thereby improving the mechanical properties of welded joints.

Solid lubricating films have great advantages in extreme operating conditions. In this research, silver (Ag) was doped into the ZrMoN composite film to develop a composite polyphase structure with enhanced mechanical and tribological properties. A series of ZrMoN–Ag composite films with different Ag content were prepared. The results show that the composition phases of the composite films are fcc-Mo2N、fcc-ZrN, and nano-crystalline fcc-Ag was dispersed in the films. The ZrMoN–Ag composite films exhibited excellent mechanical properties with a hardness of 27.6 GPa and elastic modulus of 286.8 GPa. In addition, the ZrMoN–Ag composite film with Ag content of 11.88 at.% possessed the advantage of low friction coefficient in a wide temperature range, attributing mainly to the synergetic effect of Ag phase and friction oxidation products. This work provides a promising solution for designing solid self-lubrication composite in wide temperature domain.

Due to the brittle weld joints and worsening hot cracking tendency of spray-formed (SF) 7055 aluminum alloy, they are regarded as un-weldable. In this study, TiB2–Al3Ti/7055 (MA) aluminum matrix composites manufactured by the master alloy method were used to connect SF 7055 aluminum alloy. In the as-weld state, ceramic particles refine α-Al grains in weld metal (WM) and reduce the hot cracking tendency of weld joints. The tensile properties of weld joints increased from 240 ± 5 MPa, 1.4 ± 0.24% (7055) to 284 ± 5 MPa, 4.0 ± 0.35% (MA). In the heat treatment states (T6, T76, and RRA), the mechanical properties and corrosion resistance of MA-WM are superior to 7055-WM. The tensile strength of MA-T6 (485 ± 20 MPa, 3.10 ± 0.23%) is the best of the three heat treatment states, while the corrosion resistance of MA-T76 is the best. MA-RRA gains mechanical properties similar to MA-T6 and corrosion resistance close to MA-T76.