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This paper studies a loss-averse newsvendor problem with reference dependence, where both demand and yield rate are stochastic. We obtain the loss-averse newsvendor’s optimal ordering policy and analyze the effects of loss aversion, reference dependence, random demand and yield on it. It is shown that the loss-averse newsvendor’s optimal order quantity and expected utility decreases in loss aversion level and reference point. Then, that this order quantity may be larger than the risk-neutral one’s if the reference point is less than a negative threshold. In addition, although the effect of random yield leads to an increase in the order quantity, the loss-averse newsvendor may order more than, equal to or less than the classical one, which significantly depends on loss aversion level and reference point. Numerical experiments were conducted to demonstrate our theoretical results.

To satisfy performance and long life requirements for hot forging die, Ni60-Cr 3 C 2 composite coatings were prepared on the high-speed steel W 6 Mo 5 Cr 4 V 2 using laser cladding technology. Laser clad coatings with different ratios of Ni60:Cr 3 C 2 were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), energy-dispersive X-ray analysis (EDX) and microhardness tester, respectively. Specific heat capacity and thermal conductivity were measured by Laser Thermal Constant Meter. Thermal expansion coefficient and elastic modulus were measured by Dynamic Mechanical Thermal Analyzer and Electro-Hydraulic Servocontrolled Testing System, respectively. The results indicated that Ni60＋50wt% Cr 3 C 2 composite coating had dense and homogeneous structure, as well as a metallurgical bonding with the substrate. With the increase of Cr 3 C 2 content, volume of chromium-containing compounds in the composite coating increased, microhardness increased and microstructure refined. The thermal physical parameters results showed that Ni60＋ 50wt% Cr 3 C 2 composite coating was overall worse than W 6 Mo 5 Cr 4 V 2 , but had a higher hot yield strength to alleviate hot fatigue and surface hot wear of hot forging die during hot forging and thus improve the service life of hot forging die.

The segregation of thermal diffusion salt bath chromizing process was analyzed. The experimental chromizing ingredients were prepared by the four groups A, B, C, and D. In order to study the segregation status of this case, the cooling molten salt in the crucible was removed by drilling from the heart core of molten salt. The core of molten salt was analyzed by X-ray fluorescence spectroscopy and XRD. Through the analysis, we can conclude that the Cr element deposited in the bottom was 4.51 times than the top. Chloride added to the molten salt will reduce segregation. Meantime we proposed some measures to overcome the segregation problem.