頁籤選單縮合
題 名 | 熱處理對三種國產人工林木材力學性質之影響=Effects of Heat Treatment on the Mechanical Properties of Three Domestic Plantation Wood Species |
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作 者 | 卓志隆; 陳志昇; | 書刊名 | 林產工業 |
卷 期 | 33:1 2014.03[民103.03] |
頁 次 | 頁1-12 |
分類號 | 436.187 |
關鍵詞 | 人工林木材; 熱處理材; 力學強度; Plantation wood; Heat-treated wood; Mechanical strength; |
語 文 | 中文(Chinese) |
中文摘要 | 本研究以杉木("Cunninghamia lanceolata")、柳杉("Cryptomeria japonica")以及大葉桃花心木("Swietenia macrophylla")三種人工林國產木材為研究對象,探討以170℃、190℃、210℃及230℃四種處理溫度,分別進行維持1、2、4及8h的木材熱處理後之縱向抗拉強度、縱向抗壓強度、抗彎強度(MOR)、抗彎彈性模數、至抗彎破壞為止吸收功、平行纖維方向剪力強度及勃林納硬度等性質變化並探討影響熱處理材強度之關鍵因子。結果顯示,熱處理材強度性質會隨處理溫度升高或時間增長,呈先上升後下降及逐漸下降兩種狀況,其中以縱向抗拉強度與至破壞為止吸收功的減低率較大,平均最高減低率分別為80%及90%,抗彎彈性模數(MOE)受到影響程度較低。熱處理杉木強度的減低率相對較柳杉與大葉桃花心木為低,經統計分析結果顯示熱處理溫度是影響強度的關鍵因子。依MOE與MOR關係推估熱處理材E50、E70、E90、E110等級之MOR5%下限值分別為17.05、28.90、39.75與50.97 MPa。 |
英文摘要 | The main objective of this study was to evaluate the key factor and influence of heat treatment parameters, namely temperature and exposure time on the mechanical properties of three plantation wood species including China fir (“Cunninghamia lanceolata"), Japanese cedar (“Cryptomeria japonica"), and big-leaf mahogany (“Swietenia macrophylla"). The samples were exposed to heat treatment at varying temperatures (170, 190, 210, and 230℃) for varying durations (1, 2, 4, and 8 h). Mechanical properties including tension strength parallel to grain (σ_t), compression strength parallel to grain (σ_c), modulus of rupture (MOR), modulus of elasticity (MOE), work to failure in bending (W), shear strength parallel to grain (τ), and Brinell hardness (H_B) of heat-treated samples were determined. The experimental results showed the increase in temperature and duration of heat treatment caused a gradual decline or trends of an increase in the early stage then reduction for the mechanical properties of heat-treated wood. It appears that influence of heat treatment on the reduction in σ_t and W of the samples were most pronounced. Maximum reduction values of around 80% and 90% were found for σ_t and W, respectively. Generally speaking the least affected properties is modulus of elasticity. Reduction in mechanical properties of heat-treated China fir was relatively lower than those of Japanese cedar and big-leaf mahogany. Temperature has a greater influence on the mechanical properties of heat-treated wood than those of time according to statistical analysis. The estimated values of 5% lower limit of MOR for E5, E7, E9, and E11 grades of heat-treated plantation wood were 17.05, 28.90, 39.75, and 50.97 MPa, respectively. |
本系統中英文摘要資訊取自各篇刊載內容。