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Chemical crosslinking of cellulosic fibers increases their brittleness, making them more susceptible to dry powdering. In this study, bleached eucalyptus kraft pulp (BEKP) sheets were crosslinked with glyoxal (GO) and citric acid (CA) and subsequently dry cut into powders using a Wiley cutting mill. Key variables in the powder preparation were dosages of GO and CA, as well as their respective catalysts, aluminum sulphate (alum) and sodium hypophosphite (SHP). The average fiber length of the GO and CA crosslinked pulps was reduced, at most down to 0.12 and 0.17 mm by the dry cutting, using a 0.5 mm perforated screen in the final dry-cutting stage. The powders exhibited reduced water retention, lower sedimentation volume in water, and, when dry, showed increased tapped and bulk densities. When mixed with refined BEKP, the powders enhanced dewatering during handsheet formation and improved the resulting sheets’ bulk, light scattering, and opacity, while reducing tensile strength. These findings suggest that chemically crosslinked pulp powders have potential as a bulking and dewatering aid in papermaking. Furthermore, due to their low water absorbency and presumable low abrasiveness, the powder may have potential applications beyond papermaking, such as filler of plastics, glues, and coating materials.

The paper presents the results of research on the effect produced by modern cooling methods on the chip shapes and surface roughness when finish turning of ASTM A53 and AISI 1010 low carbon steels. Dry cutting, cooling by compressed air and the Minimum–Quantity–Cooling–Lubrication (MQCL) method were compared. The MQCL method is more effective for machining low carbon steel and ensures a usable chip shape and lesser surface roughness. Depending on the cutting conditions, the efficiency of the MQCL method is 10 to 30 % higher compared to dry machining. Examples of experimental investigations about reducing the use of cooling lubricant substances in turning process can be found in the open literature [1, 2].

The paper presents the results of research on the effect produced by various cooling methods on the chip thickness ratio, shear angle and shearing force. Dry cutting, cooling by compressed air and the MinimumQuantityCoolingLubrication (MQCL) method when finish turning of carbon steel with different speeds of cutting and feed rates were compared. The investigations were performed in accordance with the Parameter Space Investigation method. The advantage of the MQCL is confirmed by lower values of the chip thickening ratio, shearing force and higher values of the shear angle. Depending on the cutting conditions, the efficiency of the MQCL method is 6 to 30% higher compared to dry machining.

Carbon fiber–reinforced polymer (CFRP) has the characteristics of high brittleness and high hardness, which easily causes delamination damage and burr damage, resulting in low hole-making efficiency, and the application of cutting fluid in the process will lead to the decrease of mechanical properties of the material. In order to improve the surface quality and processing efficiency of CFRP, an ultrasonic-assisted dry helical milling technology is proposed. Taking tool rotation speed, feed rate, pitch, and ultrasonic amplitude as optimization variables and taking minimum delamination damage, burr damage, and maximum material removal rate as objective functions, multi-objective optimization models are established through experiments and genetic algorithm, and Pareto optimal solution sets are obtained. The results show that the influence weights are in the order of pitch, tool rotation speed, ultrasonic amplitude, and feed rate for the analysis of variance of delamination damage, accounting for 38.7%, 24.9%, 20.9%, and 15.5%, respectively. The maximum weight of pitch is 29.7%, and the minimum weight of ultrasonic amplitude is 18.1%, in the analysis of variance of burr damage. Finally, multi-objective optimization models are verified by experiments, and it is concluded that the established optimization models can provide multiple parameter optimization schemes for different engineering applications with high accuracy.

Ti-6Al-4V alloy has low thermal conductivity, poor machinability, and active chemical activity. However, it is easily bonded to tool surface in the cutting process, resulting in drastic tool wear. The friction contact state and friction behavior between the tool and machined surface can be significantly improved when adopting tool with micro texture on the surface. The tools with line texture, regular hexagonal texture, and without texture on the rake face were adopted in this study. The cutting force, tool wear morphology, and friction coefficient of different type of tools are analyzed based on dry cutting test, friction, and wear test of cemented carbide and titanium alloy. The result shows that the cutting force caused by the line-textured tool is the smallest, following by hexagonal-textured tool and no-textured tool. However, large damage would happen at the cutting edge of line-textured tool as the cutting continues, while the damage of hexagonal-textured tool is relatively light. The main cutting force and feed force of the three kinds of tools increase as cutting depth increased, while decrease with the increase of cutting speed. The wear morphology of textured tool is smoother than that of no-textured tool, due to the micro texture can contain debris and reduce friction coefficient. A cutting force equation is established by ridge regression method based on actual cutting data, which provides a new idea for monitoring the tool during cutting process.

In machining operations, minimizing the usage of resources such as energy, tools, costs, and production time, while maximizing process outputs such as surface quality and productivity, has a significant impact on the environment, process sustainability, and profit. In this context, this paper reports on the utilization of advanced multi-objective algorithms for the optimization of turning-process parameters, mainly cutting speed, feed rate, and depth of cut, in the dry machining of AISI 1045 steel for high-efficient process. Firstly, a number of experimental tests were conducted in which cutting forces and cutting temperatures are measured. Then the material removal rate and the obtainable surface roughness were determined for the examined range of cutting parameters. Next, regression models were developed to formulate the relationships between the process parameters and the four process responses. After that, four different multi-objective optimization algorithms, (1) Gray Wolf Optimizer (GWO) and (2) Weighted Value Gray Wolf Optimizer (WVGWO), (3) Multi-Objective Genetic Algorithm (MOGA), and (4) Multi-Objective Pareto Search Algorithm (MOPSA), were applied. The results reveal that the optimal running conditions of the turning process of AISI 1045 steel obtained by WVGWO are a feed rate of 0.050 mm/rev, cutting speed of 156.5 m/min, and depth of cut of 0.57 mm. These conditions produce a high level of material removal rate of 4460.25 mm3/min, in addition to satisfying the surface quality with a roughness average of 0.719 µm. The optimal running conditions were found to be dependent on the objective outcomes’ order. Moreover, a comparative evaluation of the obtainable dimensional accuracy in both dry and wet turning operations was carried out, revealing a minimal relative error of 0.053% maximum between the two turning conditions. The results of this research work assist in obtaining precise, optimal, and cost-effective machining solutions, which can deliver a high-throughput, controllable, and robust manufacturing process when turning AISI 1045 steel.

Tungsten alloys have excellent properties such as high strength, high hardness, high melting point, and high specific gravity, which have been widely used in many cutting-edge scientific fields such as aerospace and military. In order to solve the problems of poor surface quality and severe tool wear in tungsten alloy cutting, conventional dry turning and electroplastically assisted dry turning with different electrical parameters were carried out to study the effects of electroplasticity on surface roughness, surface defects, tool wear, and chip morphology of W93NiFe alloy. The results showed that the electroplastically assisted dry turning process improved the surface quality of W93NiFe alloy. The surface roughness value decreases gradually with the increase of pulse voltage and reaches the minimum value at the pulse voltage of 80 V, with the maximum reduction of 38.94% compared with conventional dry turning. However, too high pulse voltage causes an increase in the surface roughness value. When the pulse voltage was increased from 80 to 90 V, the surface roughness increased by 29.63%. At a pulse voltage of 70 V, the surface roughness value did not change much for different pulse current frequency conditions. Compared to conventional dry turning, electroplastically assisted cutting reduced the degree of machined surface defects in the material and tool wear, but it could lead to the formation of built-up edge at the tool tip. After the pulsed current was applied, the chip curl radius and pitch were smaller, and it was easier to form strip chips with longer transverse lengths. The results provide a reliable reference for electroplastically assisted cutting in the future.

To further improve the cutting performance of WC/Co tools in the dry cutting of Ti-6Al-4V alloy. Experiments in dry cutting titanium alloy were carried out using micro-textured YG8 tools under different cutting speeds and depths. Three kinds of YG8 tools with the rake face machined with line groove, sinusoidal groove, and rhombic groove were adopted as the micro-texture YG8 tools. The cutting force, friction coefficient of the tool-chip contact zone, chip morphology, tool wear, and surface quality of machined titanium alloy were analyzed. The results show that the micro-textured tools can effectively reduce the wear area on the rake face and flank face, improve the wear form on the rake face, reduce the occurrence of oxidation wear, and improve the surface quality of machined Ti-6Al-4V alloy. Therefore, micro-textured tools can effectively improve cutting performance and prolong tool life. The existence of micro-texture on the tool surface has a certain influence on the tool performance. The line groove-textured tool has the best effect, followed by the sinusoidal and rhombic groove-textured tools.

Sustainable manufacturing has received great attention in the last few decades for obtaining high quality products with minimal costs and minimal negative impacts on environment. Sustainable machining is one of the main sustainable manufacturing branches, which is concerned with improving environmental conditions, reducing power consumption, and minimizing machining costs. In the current study, the performance of three sustainable machining techniques, namely dry, compressed air cooling, and minimum quantity lubrication, is compared with conventional flood machining during the turning of austenitic stainless steel (Nitronic 60). This alloy is widely used in aerospace engine components, medical applications, gas power industries, and nuclear power systems due to its superior mechanical and thermal properties. Machining was performed using SiAlON ceramic tool with four different cutting speeds, feeds and a constant depth of cut. Consequently, various chip characteristics such as chip morphology, chip thickness, saw tooth distance and chip segmentation frequency were analyzed with both optical and scanning electron microscopes. Performance assessment was performed under the investigated cutting conditions. Our results show that the tool life under MQL machining are 138%, 72%, and 11% greater than dry, compressed air, and flooded conditions, respectively. The use of SiAlON ceramic tool results is more economically viable under the MQL environment as the overall machining cost per component is lower ( $0.27) as compared to dry ($ 0.36), compressed air ( $0.31), and flooded ($ 0.29) machining conditions. The minimum quantity lubrication technique outperformed the other investigated techniques in terms of eco-friendly aspects, economic feasibility, and technical viability to improve sustainability.

This study describes the surface topography of the 17-4 PH stainless steel machined under dry, wet and near-dry cutting conditions. Cutting speeds of 150–500 m/min, feeds of 0.05–0.4 mm/rev and 0.5 mm depth of cutting were applied. The research was based on the ‘parameter space investigation’ method. Surface roughness parameters, contour maps and material participation curves were analysed using the optical Sensofar S Neox 3D profilometer and the effect of feed, cutting speed and their mutual interaction was noticed. Changes in chip shape depending on the processing conditions are shown. Compared to dry machining, a reduction of Sa, Sq and Sz parameters of 38–48% was achieved for near-dry condition. For lower feeds and average cutting speeds valleys and ridges were observed on the surface machined under dry, wet and near-dry conditions. For higher feeds and middle and higher cutting speeds, deep valleys and high ridges were observed on the surface. Depending on the processing conditions, different textures of the machined surface were registered, particularly anisotropic mixed, periodic and periodically determined. In the Sa range of 0.4–0.8 μm for dry and wet conditions the surface isotropy is ~20%, under near-dry conditions it is ~60%.