[en] CuO nanoparticles prepared by complexation precipitation method at 30 °C were used as precoating materials on a crankshaft (QT500-7) surface. In the ammonia atmosphere, copper/microalloyed gradient coating with a metal-like appearance was obtained via CuO nanoparticles redox reaction and gas nitriding at 530 °C for 3 h and 5 h, respectively. Bonding strength between the Cu coating and microalloyed layer can reach up to 34 N. The treated samples were evaluated under actual working conditions in the factory, which was placed on the bench test machine for wear resistance test (168 h and 500 h). Results indicate that the pores on the copper layer have the functions of oil storage and chip storage, which can improve the lubrication performance. Meanwhile, the copper elements was transferred on the crank (Pair grinding), reducing the wear of crank accidentally. The surface gradient composite layer of the crankshaft has better wear resistance than nitriding treatment. Compared with copper plating, the in-situ growth methods can provide a new way of preparing copper/microalloyed gradient coating without any pollution. (paper)

[en] HL-2A plasmas heated by neutral beam injection (NBI) regularly exhibit n = 1 long-lived saturated magnetohydrodynamic instabilities. A reduction in the electron density and plasma stored energy and an increase in fast ion losses are usually observed in the presence of such perturbations. The observed long-lived saturated internal mode (LLM) occurs when the safety factor profile has a weak shear in a broad range of the plasma centre with q_min around unity. It is found that the ideal interchange mode can become marginally stable due to the weak magnetic shear reaching a critical value. The LLM, due to its pressure-driven feature, is destabilized by the strong interaction with fast ions in the low-shear region during the NBI. Furthermore, for the first time it is clearly observed that the LLMs can be suppressed by electron cyclotron resonant heating (ECRH), or by supersonic molecular beam injection in HL-2A plasmas. Low-n sidebands observed during the LLM are also suppressed by increasing the ECRH power. The control of LLMs is due to the change in the magnetic shear or in the pressure profile induced by the local heating or fuelling. (paper)

[en] Highlights: • Influence of quenching and partitioning process on stainless steel was studied. • Pitting potentials of experimental steel partitioned at 350 and 450 °C were higher. • Retained austenite and M_3C carbides existed in matrix of experimental steel. • Retained austenite is beneficial for the corrosion resistance of stainless steel. - Abstract: A 0.3C–13Cr martensitic stainless steel (MSS) was subjected to quenching and partitioning (Q&P) treatment. Due to the different thermodynamic condition from the standard constrained carbon equilibrium (CCE), both the carbides precipitation and the interface migration occur during the partitioning step in the Q&P treatment. However, a sufficient amount of austenite is still retained in the Q&P treated MSS. After being partitioned at 350 °C and 450 °C, the Q&P treated MSS exhibits better corrosion resistance than the same steel treated via conventional quenching and tempering (Q–T) treatment.

[en] Highlights: • The content of Ni"2"+ in the Li layer decreases with the Li-excess increase in Li_1_+_xNi_0_._5Co_0_._2Mn_0_._3O_2 (x = 0, 0.02, 0.04, 0.06, 0.08) materials. • Li_1_._0_8Ni_0_._5Co_0_._2Mn_0_._3O_2 has the largest diffusivity value in all samples. - Abstract: Layered Li_1_+_xNi_0_._5Co_0_._2Mn_0_._3O_2 (x = 0, 0.02, 0.04, 0.06, 0.08) materials were synthesized using the co-precipitation method. Rietveld refinements measurements reveal that the concentration of Ni"2"+-3b ions decreases from 0.06 to 0.043, with x changing from 0.02 to 0.08. The initial coulombic efficiency improves with the increase in the content of Li-excess because the content of Ni at the 3b site decreases with the increase of Li-excess in the samples from 0 to 0.08. The analysis indicates that Li_1_._0_8Ni_0_._5Co_0_._2Mn_0_._3O_2 exhibits the largest diffusivity value due to the dependence of the diffusion coefficient of lithium ions on the content of Ni in the 3b sites