Papers by Keyword: Orthogonal Experiment

Abstract: Titanium alloy fasteners are extensively used in advanced fields such as aerospace due to their corrosion resistance, high-temperature endurance, low density, and high strength-to-weight ratio. In practical applications, fatigue failure is the primary failure mode for these fasteners. Besides the operational environment, the manufacturing process, especially surface treatment techniques, plays a crucial role in affecting the fatigue life of titanium alloy fasteners. This paper examines the impact of three surface treatment processes-rolled fillet, pulsed anodization, and molybdenum disulfide coating－on the fatigue life of titanium alloy fasteners through orthogonal experiments. The study finds that both rolled fillet and molybdenum disulfide coating significantly influence the fatigue life. This effect is associated with residual stresses, where compressive residual stress initially increases with rolling pressure but subsequently decreases, and reduces as the thickness of the molybdenum disulfide lubricating film rises.

Abstract: To improve the yield and quality of pearls in freshwater pearl culture and the survival rates after nucleus implanting surgery, pearl farmers used artificial pearl nuclear transplantation techniques to raise pearls. To address the common problem of Staphylococcus aureus and Escherichia coli infection in oyster farming, a new prophylactic method by using compound antibiotics to prepare the medicine coated pearl nucleus was put forward based on existing research results of the nanosilver antibacterial nucleus. Single-factor experiment, multi-factor experiment, orthogonal experiment, SPSS analysis of variance was used to optimize the antibacterial formulation on the assumption that the contaminated probability of these two pathogenic bacteria was the same. The result showed that the optimal ratio of compound antibiotics was 0.0075g/ml of the flavomycin solution and 0.01g/mL of the terramycin solution; the inhibition zones diameter of both pathogenic bacteria was more than 2.6cm in vitro, which was higher than the nanosilver antibacterial nucleus of 0.9cm in vitro. Indicating that the addition of this compound antibiotic formula for the nanosilver antibacterial nucleus could reduce the usage of antibiotics under the premise of maintaining antibacterial effectiveness, and could preferably inhibit the pathogenic microorganisms in the postoperative infection period. This also indicates that compound antibiotics coated antibacterial nanosilver nucleus would be applied more widely.

Abstract: The effects of different process parameters on the microstructure and mechanical properties of Zr-based bulk metallic glass were studied by using four factors and four levels of orthogonal experiment. Through the observation and analysis of the X-ray diffraction pattern, room temperature compressibility, microhardness distribution and transmission electron micrograph of the [Zr_0.72-x(Cu_0.59Ni_0.41)_0.28+x]_88-yAl_12+y (atomic percent) amorphous alloy with different process parameters, the results show that the compressive strength of the amorphous alloys with composition of [Zr_0.73(Cu_0.59Ni_0.41)_0.27]₈₈Al₁₂ and [Zr_0.73(Cu_0.59Ni_0.41)_0.27]₈₇Al₁₃ amorphous alloy under the corresponding processing parameters has reached 2411MPa and 1993MPa, and the plastic strain of the alloys is 33.8% and 19.3%. At the same time, through orthogonal analysis, in the four process parameters, the superheat temperature of the melt during the preparation of the alloy mainly affects the compressive strength of the alloy, while the cooling rate of the melt during the preparation of the alloy has a great influence on the plastic properties of the alloy.

Abstract: The demolished concrete lumps (DCLs) have been demonstrated to replacement partial coarse aggregates when casting concrete. However, few studies had focused on the sensitivity of factors affecting mechanical behavior of slender square steel slender columns filled with DCLs and fresh concrete (FC) under axial compression. This research was carried out on the basis of Bo Wu's study. The Orthogonal design method was adopted in this experiment. The experimental studied involved 12 Concrete-Filled Steel Tube (CFST) columns. Each columns diameter was 159mm, the length of specimens was 2000, 2200 and 2400 mm. The Diameter-to-thickness (D/t) ratio was 79, 53 and 40. The replacement ratio of FC by DCLs was 0, 20, 40 and 60%. Test results indicated that the slenderness ratio was the most sensitive factor on the bearing capacity of slender columns under axial compression, followed by D/t ratio, and the DCLs replacement ratio was smallest factor. The ultimate bearing capacity decreased slightly with increasing DCL replacement ratio. The DCLs had slightly affect on the mechanical performances of slender CFST columns. the code CECS 28:2012 was used to calculate the bearing capacity of slender CFST columns filled with DCLs under axial compression.

Abstract: The orthogonal experiment method is used in optimal design of laser cladding, such as laser power (P), scanning speed (SS), powder feeding rate (PFR) and shielding gas velocity (SGV) etc. Both the dilution rate and the aspect ratio are investigated by comprehensive scoring method, which transforms multi-index into single index. In view of the nonlinear characteristics of laser cladding process parameters, the optimum level of each factor based on interaction effect is obtained by analyzing binary tables. Finally, the relationship between the laser cladding process parameters and the two indexes (the dilution rate and the ratio of width to height of coating) is obtained. This method has potential applications for the further investigating on the laser cladding process rules.

Abstract: Soybean protein isolate (SPI) is widely used in food industry because of its high protein nutritional function and good functional characteristics. However, due to the effect of amino acid composition and spatial structure on natural protein, its practical application is greatly limited. So it needs to be properly modified to meet the needs of production. In this study, SPI was used as substrate to explore the most suitable modification conditions by using complex enzymes (flavor protease, neutral protease, alkaline enzyme and transglutaminase) enzymolysis and then TG enzyme cross linking, in order to obtain SPI products with both solubility and gel as a special protein isolate for surimi products. The results show that: through the single factor experiment and orthogonal experiment, the optimized conditions of gel strength were determined: flavor protease: neutral protease: alkaline enzyme 1:1:2, pH 7, enzymolysis temperature 45°C, enzymolysis time 30 min. The optimized conditions of solubility: flavor protease: neutral protease: alkaline enzyme 1:2:2, pH 7, enzymolysis temperature 55°C, enzymolysis time 60 min. The result of orthogonal experiment: the optimized conditions was that flavor protease: neutral protease: alkaline enzyme 1:1:2, pH 7, enzymolysis temperature 55°C, enzymolysis time 60 min. The gel strength of products was 35.45 g, decreased 5.33% with control; Solubility was 36.24%, increased 54.01% with control. The modified SPI has excellent gel and solubility, and can be further applied to surimi products industry. And the results of this study provide a theoretical basis for its further application in surimi products.

Abstract: The purpose of this paper is to explore the potential of tablet manufacturing technology combined with 3D printing technology. The acetaminophen raw materials used for 3D printing are formulated in a clean environment according to the actual amount. And homemade material mixed-type three-dimensional printer is used to print double-layer acetaminophen tablets. In this paper, the factors influencing the quality of the tablet were explored by orthogonal experiments, and the optimal parameters were obtained. In order to determine whether the tablet meets the quality requirements, the hardness, friability and dissolution profiles of the 3D printing tablets were determined by the test instrument.

Abstract: Integrated with orthogonal design method and numerical simulation, injection molding process of the Y-type electrical connectors was conducted to study the influence of process parameters on volume shrinkage rate and maximum warpage, which are regarded as product quality indices. The multi-indices valuation model for the main influencing factors of the process is developed. The influencing sensitivity to the multi-objective of the processing parameters, such as melt temperature, mold temperature, injection time and holding pressure, is determined by range analysis. Through analyzing the diagrams of influential factors, the optimized process parameter diagram is obtained and verified by simulation. The optimum parameters minimizing the warpage defect and shrinkage are: melt temperature (528K), mold temperature (338K), filling time (0.6s), holding pressure (100%) and holding time (10s). The results show that it is effective to balance the impact of process parameters on the shrinkage and warpage. The work can provide optimal design and process reference for the quality control and assembly precision.

Abstract: The homogenization treatment was performed to fibrillate Lyocell fiber, and then the effects of different factors including NaOH concentration, homogeneous time, temperature and bath ratio on the fibrillation degree of Lyocell fiber were investigated through the orthogonal experiment. Various characterization techniques were employed to compare the fibrillation degree of Lyocell fiber. The polarized light microscope (POM) and scanning electron microscope (SEM) were used to observe the appearance of the fiber after different treatment, and the results showed that it was a quick and efficient approach to obtain the fibrillated Lyocell fiber by homogenization treatment, and the fibrillation degree of fibers varied with different treatment conditions. The results of water retention value (WRV) and the characteristic parameter of the fibrillation degree revealed that the ranking of factors affecting the fibrillation degree of fibers was NaOH concentration > homogeneous time > temperature > bath ratio, using the extreme difference analysis and variance analysis methods. The degree of fibrillation was influenced dominantly by NaOH concentration, rather than any other three factors. By means of BET test, the specific surface area of treated fiber showed a similar trend with WRV, and they matched well with fibril amount on the fibers observed by SEM.

Abstract: According to the working principle of the lifting film shovel for the residual plastic film of bed planting, the structure of the lifting film shovel was designed. Based on the soil dynamics model, the finite element analysis of the static strength of the lifting film shovel was carried out by using ANSYS software. The results show that the stress and deformation of the lifting film shovel increase with tilt angle, and the maximum stress point is on the edge of the mounting holes. When the tilt angle is 46°, the maximum stress is 82.4 Mpa, and the maximum deformation is 0.901 mm. The effects on the hilling height of the travelling speed of the equipment, the tilt angle of the lifting film shovel and the number of the bars were researched by the orthogonal regression experiment of three factors and five levels. The results of the experiment indicate that the effect of tilt angle on the hilling height is larger than that of the traveling speed of the equipment and the number of the bars, and the structure parameters and operating parameters were optimized by the experiment, thus, the optimal tilt angle of the lifting film shovel is 26⁰ and the optimal number of the bars is 2.