对烤箱干燥木材密度测量的影响因素
Lukas Emmerich1, Moritz Kampherm2, Christian Brischke3
1Wald und Holz NRW-Centre of Forest and Wood-Based Industries (FBV), Team Wood-Based Industries, Carlsauestraße 91A, D-59939 Olsberg, Germany.
Materials (Basel, Switzerland)
|September 27, 2025
概括
确定木材密度需要仔细干燥,以避免挥发性化合物的错误. 在木材科学中,较低的温度 (低于103°C) 对于准确的绝对干量测量至关重要.
科学领域:
- 木材科学 木材科学 木材科学
- 材料科学 材料科学 材料科学
- 林业林业 林业 林业 林业
背景情况:
- 木材密度对于解释木材的物理,机械,声学和热性能至关重要.
- 精确的密度测定对于材料表征和质量控制至关重要.
- 标准重力测量方法需要烤箱干燥到绝对干燥状态,通常在103°C.
研究的目的:
- 研究不同干燥条件 (温度和持续时间) 对木材样本达到绝对干燥状态的影响.
- 在不同的条件下评估烤箱干燥密度测量的准确性.
- 识别标准木材密度测定协议中的潜在错误来源.
主要方法:
- 各种软木和硬木物种的木头标本经受了不同的干燥温度 (60°C,80°C,103°C) 和持续时间 (8,16,24,48小时) 的影响.
- 在干燥后测量了绝对干燥质量和尺寸.
- 分析了与挥发性元件蒸发和测量不准确性相关的潜在错误.
主要成果:
- 在103°C的标准烤箱中干燥48小时,由于样品处理和尺度偏差,可能会引发重大错误.
- 干燥温度低于103°C对于准确确定绝对干质量和尺寸至关重要.
- 挥发性木材组件可以导致错误的高残余水分含量,作为额外的错误来源.
结论:
- 优化干燥条件,可能使用较低的温度,对于准确的木材密度测定是必要的.
- 挥发性化合物的存在需要在烤箱干燥过程中仔细考虑.
- 需要精细的协议来最大限度地减少重力测量木材密度测量的错误,以进行可靠的材料属性分析.
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