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"ABSTRACT <br/>The current challenges of the small-scale fiber producers such as unavailability of cutting machines for natural fibers; low production rate; and non-uniform length of cut fibers if done manually, prompted the researcher to develop an appropriate cutting technology to realize improved productivity and efficiency of the cutting process for the growing demand of cut fibers in various applications ranging from automobiles, furniture, packaging and construction. This study employed advanced engineering design, a sophisticated process of modelling, simulation, visualization, analysis design, prototyping, testing and fabrication. Testing the developed prototype revealed that the target feed rate of 45 mm/sec, 50 mm/sec and 55 mm/sec for a target length of 10mm, 30 mm and 50 mm length of cut fibers were achieved. The cutting time was 0.229 seconds for all lengths of cut fibers with a cutting speed of 0.3493 m/s which is higher than the target of 2.5 m/s. An applied pressure to the pneumatic cylinder of 6.5 bars was established as the minimum working pressure. The maximum thickness of natural fiber that should be fed in the conveyor for cutting was 2.3 mm. The cutting rate for 10 mm, 30mm and 50mm using abaca were 1.90 grams/minute, 4.60 grams/minute and 6.30 grams/minute, respectively. The cutting rate for 10 mm, 30mm and 50mm for banana were 2.04 grams/minute, 5.25 grams/minute and 7.13 grams/minute, respectively. The cutting rate for 10 mm, 30mm and 50mm for buntal fiber were 2.65 grams/minute, 8.98 grams/minute and 10.9 grams/minute, respectively. These values are higher than the target cutting rate. The cutting efficiency ranges from 97.4 to 100% which exceeded the target of at least 95%. The cutting performance of the system showed that it is accurate, efficient and highly acceptable. After determining the performance target indicators of the automated cutter, machine acceptability was then evaluated using a developed survey questionnaire. The overall average value of machine acceptability was 4.7975, interpreted as highly acceptable. Machine acceptability was in terms of design and construction. perceived functionality, perceived accuracy and reliability, and perceived industrial applicability and safety. The economic feasibility of the project resulted to a rate of return of 67.925%, payback period of 1.3 years, and benefit-to cost ratio of 1.4148. Thus, the machine is considered technically acceptable and economically feasible. The operation and maintenance manual articulating the operation and maintenance procedures was developed to serve as guide to possible users. Given the opportunity to fully utilize this automated cutter by the target end users, it can reduce labor costs and create a positive impact on profitability. the holding time is set as a fixed value, I:he grain size of GH4065 superalloy will grow with the increase of temperature, and the grain growth rate increases with the increase of tempevature.Finally, by using Origin data analysis software to calculate and analyze the experimental data of grain growth, the grain growth model of GH4065 superalloy is established. (5) The forging design of the turbine disk is completed according to the part drawing of the turbine disk, and the forming process route of heating and heat preservation - transfer - free forging and upsetting - transfer - secondary heating and heat preservation - transfer - die final forging and pressure holding - cooling is fo,mulated. (6) The microstricture evolution of GH4065 high temperature turbine disk forging process is simulated by multi-scale vortex force finite element method. According to the numerical simulation results, the evolution law of grain size of turbine disk in the stages of heating, heat preservation, transportation, upsetting, final forging and air cooling is deeply and carefully analyzed. Finally, the detailed evolution law and distribution of grain size in each part of turbine disk forging are obtained. (7) According to he forming process test of turbine disk, the forming of turbine disk is completed. Through the sampling and microstructure comparison of the actually formed turbine disk, it is found that the average grain size of the numerical simulation of each part is close to the average grain size of the actual forging, and the error is no more than 13.5%. It is verified that the numerical simulation of microstructure has high reliability. <br/>Keywords: Turbine disk, GH4065 nickel base superalloy, Artificial neural networks, Dynamic recrystallization, Grain growth, Molding process, Numerical simulation -Authors Abstract.<br/>"<br/> |