연기지중 (鉛基地中) 에 강섬유를 삽입해서된 복합재료의 제조에 관한 연구 = A Study on the Fabrication of Lead-Composite material Reinforced with Steel Fiber

국문 초록 (Abstract)

鉛基地中에 solder-coating을 한 綱纖維와 하지 않은 鋼纖維를 삽입해서 만든 두 種類의 複合材料에 對해서, 機械的成質, 塑性擧動 및 破斷樣相을 調査하였으며, 同時에 燒鈍溫度에 따른 鋼纖維의 機械的性質도 檢討되었다.
solder-coating을 한 鋼纖維를 가지고 만든 複合材料는 複合則에 의한 引張强度値를 잘 나타내지만, solder-coating을 하지 않은 鋼纖維를 가지고 만든 것은 複合則에 의한 强度보다 약간 낮은 값을 나타낸다. 複合材料의 stress-strain曲線은 crack 發生區域과 crack 傳播區域으로 區分되어 질 수 있으며, solder-coating한 鋼纖維를 가지고 만든 複合材料의 stress-strain 曲線은 crack發生區域에서 連續性을 나타내지만, solder-coating을 하지 않은 鋼纖維를 가지고 만든 複合村料의 stress-strain 曲線은 不連續性을 나타낸다. solder-coating을 한 鐵纖維를 가지고 만든 複合材料에서는 fiber가 全部 破面上에서 破斷되지만, solder-coating을 하지 않은 것의 複合材料에서는 fiber의 破斷이 random한 位置에서 일어난다.
綱纖維의 引張强度는 燒鈍溫度에 對해서 3段階로 나누어진다. 第1段階인 25°∼300℃의 區間에서는 거의 一定한 引張强度値를 나타내며, 第2段階인 300°∼600℃의 區域에서는 溫度의 增加와 더불어 引張强度가 急激히 감소한다. 그리고 600℃以上인 第3段階에서는 溫度에 關係없이 거의 一定한 引張强度値를 나타낸다.

다국어 초록 (Multilingual Abstract)

Two types of lead-composite reinforced with steel fiber were prepared by a casting method; one was fabricated with solder-coated steel fiber, and the other the solder-ancoated steel fiber. The mechanical properties, plastic behaviors, and fracture modes of these composites have been studied, and the mechanical properties of the steel fiber have also been investigated on the variation of annealing temperature.
The ultimate tensile strength of the composite with solder-coated steel fiber is in good agreement with the theoretical value shown by rule of mixture. However, the value of tensile strength of the composite with solder-uncoated steel fiber shows a slight deviation from the value of the rule of mixture. The stress-strain curves of all the composites can be divided into two regions, corresponding to crack initiation and crack propagation. The stress-strain curve of the composite with solder-coated steel fiber shows a continuity in the former region, however that of the composite with solder-ancoated steel fiber shows a discontinuity in the same region. In the case of composite having solder-coated steel fiber the fracture of steel fiber occurs necessarily at the fracture surface of composite, while in the case of the latter composite with solder-uncoated steel fiber the fiber fractures randomly in the composite.
The variation in ultimate tensile strength of the steel fiber with annealing temperature consists of three stages; first stage ranged from 25°to 300℃ shows a nearly constant strength, second stage from 300° to 600℃ has a strength decreased rapidly with the increase in temperature, and third stage which is above 600℃ shows a nearly constant value of strength as in the case of the first stage.