The machined surface integrity of blades is of utmost importance in the power equipment manufacturing industry. Recently, many blade accidents have been attributable to the misuse of cutting fluids that were necessary in the actual machining of difficult-to-cut materials, but the effect of the cutting fluid on surface integrity and service performance has been persistently neglected. In this article, an investigation into the effect of cutting fluids on the surface quality of a typical blade material was undertaken, combined with properties of two universal cutting fluids. Element composition, surface morphology, residual stress and hardness of the machined surfaces were investigated. The results indicated that cutting fluids could not reduce cutting forces in precision machining. There were some places where local and irregular elemental Cr loss was incurred when machined with the additive Cl, and the depth of Cr loss was 1-2 mm. The machined surface under CF-206 was smooth, and the roughness of CF-210 was the highest. The tensile residual stresses of dry cutting were the highest, whereas those of CF-210 were the lowest. Surface work hardening under cutting fluids was higher, with depths of 20-30 mm. These results are significant for the control of precision machined surfaces and subsurfaces of blades with high integrity and service performance.

Compared with CNT film detectors, the CsxWO3–CNT composite film detector shows a significantly enhanced photoresponse from visible light to short-wave infrared region, with an average increase of 400% in responsivity and 549% in specific detectivity.

As the steam turbine rotor works in extreme conditions of high temperature, pressure, speed, and load, better material performance and machined surface quality are highly demanded. Fe-based superalloy is a kind of typical difficultto-cut material that is widely used as steam turbine rotors, and cutting fluid is necessary during its machining process. However, many accidents occurred for the misuse of cutting fluids. The effect of cutting fluids on material characteristics and physical mechanical properties cannot be ignored. In this article, an experimental research was taken on the effect of cutting fluids on corrosion property and turning surface quality of a typical rotor material. Tafel curves, electrochemical impedance spectroscopy, surface morphology, and residual stress of machined surfaces were investigated. The results were explained integrating with physical and chemical properties of two cutting fluids. It indicated that the cutting fluid had an obvious effect on the corrosion property and machined surface quality of Fe-based superalloy. The material surface may be corroded after long-time exposure to cutting fluids. The lubricating property of cutting fluids has a great effect on surface morphology and residual stress, which may affect product lifetime and surface performance.

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The shale of the lower Cambrian Niutitang formation in northwestern Hunan is an ideal reservoir for shale gas. There is a close connection between borehole stability and drilling fluid in shale gas drilling. Ionic stabilizer is a new type of stratum consolidation agent that inhibits the hydration expansion of clay minerals and improves mechanical strength of the borehole. The traditional idea of pore wall protection is to use drilling fluid additives to prevent shale from interacting with water. However, ionic stabilizer can change the hydrophilic of clay minerals in shale, making the particles become hydrophobic and dense, therefore, the formation stability can be enhanced simultaneously. The material used in this paper is different from the normal ionic stabilizer, some chemical bonds that have been changed in the new material called enhanced normality ionic (ENI) stabilizer. This paper utilized the shale samples those obtained from Niutitang formation to study the connection between ENI and the mechanical properties of shale. Mechanical tests and microscopic pore tests were performed on different samples which were soaked in water and the ENI with different concentrations. It has been found through tests that ENI can inhibit the development of shale pores, and as the concentration increases, the inhibition increases. In addition, as the ENI concentration increases, the uniaxial compressive strength and Young’s modulus of the shale increase, and the ratio of stability coefficients decreases. It can be concluded that the ENI can improve the mechanical strength of carbon shale, and prevent the development of rock damage. Moreover, it can improve the ability of rock to resist damage, and enhance borehole stability initiatively.