| Summary: | 博士 === 國立中興大學 === 生物產業機電工程學系 === 92 === This study seeks to establish and analyze the mathematical models of the plowing force and trajectory curve for tiller blades and cultivation blades of a rotary. Both blades are widely used in Taiwan. To ensure good efficiency and uniform resistance of the plow to soil, the blade must be protected from intertwisting. The theoretical and calculated cutting angles are 85.88ºand 85.10º, the edge-curve angles are 55.00º and 56.18º. The rear of well designed plowing blade does not cause any friction with the soil. The curve of plowing shows that when the relief angle of the tiller blades is 25º, the turning and the throwing have good performance. When the relief angle of the plowing blade is 10º, the impact force and the crashing force of the blade into the soil will be minimized during plowing.
Under the same condition of soil, the different accelerations agree with the curves drew by different relief angles. The tiller blades developed by local companies are suitable to the plowing environment in Taiwan. The high attrition causes too much operation cost for soil preparation. Therefore, it is necessary to apply alloy powder spray-welding technology to improve the attrition as well as to increase the stability of materials, and then the lift of the blade can be extended. Consequently, the quality of the soil can be maintained.
The high attrition causes too much operation cost for soil preparation. The purpose of this study is to apply the Nickel-Base alloy powder welding technique to the blades of tillers. In order to measure surface temperature of coated blade, this research tried to use designed alloy powder spray-welding mechanism to precede the surface hardening for the blades, and to use the infrared thermal imager to collect the instant heat image and its radiant temperature. Experimental results showed that, at the measure spots, both the instant heat image displayed in the thermal imager and the surface temperature of the heat radiation collected after eight seconds consistent with the conclusions addressed by other foreign researchers. At the same time, two sets of heat radiant temperatures obtained from the thermal imager were uniformly distributed over two pieces of tiller blades. Therefore, it can be proved that the coating surface of the tiller blades treated with alloy powder welding would have more uniform, precise and stability when using the alloy powder spray-welding mechanism developed in this study.
In the SRV experiment, the duration of attrition for the coating and the abrasive parameter has shown that SUP-HF behaves better than SUP-F. The SUP-HF also has better reaction to the anti-oxidize function. The hardness parameter (Hv) on the coating is 691-702. The adherence after compression has a grade of A-class on the SEM chart. There is no significant difference on overall parameters for both specimens. The results have shown that, the SUP-HF blades performed excellently to the sandy-loam 45ha and stone gravel soil 65ha plowing; by replacement of 168 tiller blades at the basis of same abrasives. The plowing capacity sandy and stone of SUP-HF is 2.6 larger than SUP-H. Respectively the iron residues remained in the soil is less than 24,360g and 24,347g. The efficiency of the SUP-HF blades is undoubtedly confirmed.
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