Investigating the Contact Responses of the Roller Cavity Surfaces in the Compressor Blade Rolling Process

The investigation of the contact responses is the key for evaluating the local wear of dies in the plastic forming process. This paper investigated the contact load distributions and evolutions of the roller cavities in the compressor blade rolling process by the FEM. It was the first study to quantify the distributions and evolutions of the contact responses for rolling irregular components. The results indicated that the maximum contact pressure is generally present at the center of the contact interfaces, and the magnitudes of contact pressure decreased with evolution of the blade rolling process. The rolling contact interfaces can be divided into the backward slip zone, the stick zone, and the forward slip zone based on the shear stress distributions. The stick zone was a narrow belt which separated the forward and the backward slip zone, and the shear stress in the stick zone was nearly zero. The shear stress magnitudes in the forward slip zone were smaller than those in the backward slip zone, and the directions of shear stress in forward and backward slip zones were adverse. The magnitudes of shear stress over the forward and backward slip zones decreased with evolution of the blade rolling process. The distributions of local sliding were in a V-shape, the local sliding in the stick zone was nearly zero, and the bigger sliding in backward and forward slip zones was present at the boundaries of rolling entrance and exit sections. The local sliding velocity magnitudes in the backward slip zones were always bigger than those in the forward slip zones, and the magnitudes of local sliding at the rolling entrance sections were bigger than those at the rolling exit sections. In general, the local sliding velocity magnitudes increased firstly and decreased sharply at 2T/3. The current paper develops the distributions and evolutions of contact responses in the blade rolling process. The contact responses can be used for studying the wear of roller cavities to avoid the accuracy inconsistency of the shaped blade

An integration system for investment An integration system for investment turbine blade

An integration system was developed to satisfy the need of information integration in the process of designing, investment casting and monitoring aero-engine’s turbo blade. The general architecture is detailed presented in this paper. The system mainly comprises of product master model, design information management, anti-deformation design of mould cavity, intelligence mould design and blade testing. The developed system can manage mould design and blade test data fl ow, optimize mould design process and achieve the goal of integration design

Laser Manufacturing of Superwetting Oil–Water Separation Materials: A Review

The frequent occurrence of oil spills and the massive discharge of oily wastewater pose a significant threat to sustainable and healthy human development. Therefore, it is of importance to effectively separate oil–water mixtures. Inspired by nature, many superwetting surfaces/materials for oil–water separation have been developed in recent years. However, these surfaces/materials are subject to certain limitations and are unable to fully meet practical needs. With the advancement of laser technology, a novel solution has been provided for fabricating superwetting oil–water separation materials. Based on the design theory and separation mechanism, this paper summarizes the research progress of the laser-fabricated superwetting surfaces/materials for oil–water separation in recent years. First, the basic wetting theory, design strategy, and oil–water separation mechanism of the laser-fabricated materials are introduced in detail. Subsequently, the laser-fabricated oil–water separation materials, including superoleophilic/superhydrophobic materials, superhydrophilic/superoleophobic materials, and materials with reversible or superamphiphilic wettability, are systematically summarized and analyzed. Finally, the challenges and future research directions of laser-fabricated superwetting oil–water separation materials are discussed

A Study on Cutting Force of Machining In Situ TiB2 Particle-Reinforced 7050Al Alloy Matrix Composites

In situ TiB2 particle-reinforced 7050Al alloy matrix composites are a new category of particulate metal matrix composites with improved mechanical and physical properties. At present, the study of machining in situ TiB2/Al composite is limited and no specific study has been presented on cutting force. Based on previous work, experimental investigation of cutting in situ TiB2/Al composite was carried out in this study to investigate the cutting force, shear angle, mean friction angle, and shear stress. The results indicated that the feed rate, instead of cutting speed, has a significant influence on the shear angle, mean friction angle, shear stress, and forces, which is different from cutting ex situ SiC/Al composites. Meanwhile, based on Merchant’s theory, a force model, which consists of chip formation and ploughing force, was established to have a better understanding of force generation. A comparison of the results show an acceptable agreement between the force model and experiments. Additionally, at varying feed rates, the linear relationship between the shear angle and mean friction angle is still suitable for cutting in situ TiB2/7050Al alloy composites

Fabrication of a Janus Copper Mesh by SiO₂ Spraying for Unidirectional Water Transportation and Oil/Water Separation

Massive discharge of oily wastewater and frequent occurrence of offshore oil spills have posed an enormous threat to the socioeconomic and ecological environments. Janus membranes with asymmetric wettability properties have great potential for oil/water separation applications and have attracted widespread attention. However, existing Janus membranes still suffer from complex and costly manufacturing processes, low permeability, and poor recyclability. Herein, a novel and facile strategy was proposed to fabricate a Janus copper mesh with opposite wettability for unidirectional water transport and efficient oil/water separation. The hydrophilic side of the Janus copper mesh was prepared by coating it with Cu(OH)2 nanoneedles via a chemical oxidation method. The hydrophobic side was fabricated by coating it with hydrophobic SiO2 nanoparticles via a facile spraying method. The as-prepared Janus copper mesh showed asymmetric surface wettability, which can achieve unidirectional water transport and efficient oil/water separation with excellent recyclability, exhibiting great application potential for droplet manipulation and wastewater purification

Fabrication of a Janus Copper Mesh by SiO₂ Spraying for Unidirectional Water Transportation and Oil/Water Separation

Massive discharge of oily wastewater and frequent occurrence of offshore oil spills have posed an enormous threat to the socioeconomic and ecological environments. Janus membranes with asymmetric wettability properties have great potential for oil/water separation applications and have attracted widespread attention. However, existing Janus membranes still suffer from complex and costly manufacturing processes, low permeability, and poor recyclability. Herein, a novel and facile strategy was proposed to fabricate a Janus copper mesh with opposite wettability for unidirectional water transport and efficient oil/water separation. The hydrophilic side of the Janus copper mesh was prepared by coating it with Cu(OH)2 nanoneedles via a chemical oxidation method. The hydrophobic side was fabricated by coating it with hydrophobic SiO2 nanoparticles via a facile spraying method. The as-prepared Janus copper mesh showed asymmetric surface wettability, which can achieve unidirectional water transport and efficient oil/water separation with excellent recyclability, exhibiting great application potential for droplet manipulation and wastewater purification

Fabrication of a Janus Copper Mesh by SiO₂ Spraying for Unidirectional Water Transportation and Oil/Water Separation

Massive discharge of oily wastewater and frequent occurrence of offshore oil spills have posed an enormous threat to the socioeconomic and ecological environments. Janus membranes with asymmetric wettability properties have great potential for oil/water separation applications and have attracted widespread attention. However, existing Janus membranes still suffer from complex and costly manufacturing processes, low permeability, and poor recyclability. Herein, a novel and facile strategy was proposed to fabricate a Janus copper mesh with opposite wettability for unidirectional water transport and efficient oil/water separation. The hydrophilic side of the Janus copper mesh was prepared by coating it with Cu(OH)2 nanoneedles via a chemical oxidation method. The hydrophobic side was fabricated by coating it with hydrophobic SiO2 nanoparticles via a facile spraying method. The as-prepared Janus copper mesh showed asymmetric surface wettability, which can achieve unidirectional water transport and efficient oil/water separation with excellent recyclability, exhibiting great application potential for droplet manipulation and wastewater purification

Fabrication of a Janus Copper Mesh by SiO₂ Spraying for Unidirectional Water Transportation and Oil/Water Separation

Massive discharge of oily wastewater and frequent occurrence of offshore oil spills have posed an enormous threat to the socioeconomic and ecological environments. Janus membranes with asymmetric wettability properties have great potential for oil/water separation applications and have attracted widespread attention. However, existing Janus membranes still suffer from complex and costly manufacturing processes, low permeability, and poor recyclability. Herein, a novel and facile strategy was proposed to fabricate a Janus copper mesh with opposite wettability for unidirectional water transport and efficient oil/water separation. The hydrophilic side of the Janus copper mesh was prepared by coating it with Cu(OH)2 nanoneedles via a chemical oxidation method. The hydrophobic side was fabricated by coating it with hydrophobic SiO2 nanoparticles via a facile spraying method. The as-prepared Janus copper mesh showed asymmetric surface wettability, which can achieve unidirectional water transport and efficient oil/water separation with excellent recyclability, exhibiting great application potential for droplet manipulation and wastewater purification

Experimental study on creep-feed grinding burn of DD9 Nickel-based single crystal superalloy

Aiming at the problem of grinding burns on the third-generation single crystal superalloy DD9, a three-factor and five-level experiment is designed in this paper. From the perspectives of surface morphology, microhardness and microstructure, the effect of grinding process parameters on grinding burns are studied. The experimental results show that: when the workpiece feed speed is less than 250 mm/min, the grinding surface roughness Ra changes slightly around 0.8 μm, and the surface quality is good. When the feed speed is more than 250 mm/min and the grinding depth is more than 1.0 mm, the temperature in the grinding area rises sharply, the grinding lines are destroyed, grinding defects such as coating and pits appear, and the surface of the workpiece burns. The surface and surface of DD9 alloy are work hardened by slow feed grinding. The microhardness range is 400 to 600 HV, the depth of hardened layer is 50 to 110 μm, and the thickness range of plastic deformation layer is 1 to 10 μm. The recommended combination of DD9 grinding process parameters is: grinding wheel linear velocity vs=20 m/s, feed speed vw=250 mm/min, grinding depth ap=0.6 mm