光学学报, 2016, 36 (4): 0412001, 网络出版: 2016-04-05
连铸坯表面发射率的测量研究
Research on Measurement of the Surface Emissivity of Casting Billets
测量 铸坯发射率 氧化层 辐射测温 不确定度 measurement emissivity of casting billet oxide film radiation thermometry uncertainty
摘要
铸坯表面发射率是影响铸坯表面温度测量的一项重要的物理参数。利用辐射能比较测量发射率的方法,研制了一套高温铸坯发射率测量装置,其主要由加热系统、角度旋转系统、温度检测系统、真空控制系统以及背景辐射屏蔽系统等5 部分组成。利用该装置测量了GCr15 钢在不同角度、不同温度及不同氧化程度下的表面发射率。研究表明:角度增加对发射率的影响具有先增大后减小的变化规律;发射率会随着氧化程度的加深而变大,并且发射率极值点所对应的角度逐渐减小;随着温度的增加,发射率会随之增大,但是当温度超过1000 ℃后,其对发射率的影响较小。当温度为1000 ℃以上时,深度氧化的GCr15钢发射率的最大不确定度为0.0205。
Abstract
Surface emissivity of casting billets is an important parameter that affects the temperature measurement on the billets. In this paper, an experimental apparatus is established by the method of radiation energy comparison. The apparatus consists of a heating system, an angle rotating system, a temperature detection system, a vacuum control system and a background radiation shielding system. The emissivity of GCr15 steel at different angles, temperatures and oxidations is measured by this apparatus. Research shows that emissivity increases first and then decreases with the increase of the angle. Emissivity increases with the increasing oxidation, and the angel of the maximum emissivity is gradually reduced. In addition, emissivity increases with the increasing temperature but the influence of the temperature is limited once the temperature is over 1000 ℃. At last, the measurement uncertainty is analyzed and the maximum emissivity uncertainty of the deep oxidized GCr 15 steel is 0.0205 when the temperature is above 1000 ℃.
王鹏, 谢植, 胡振伟. 连铸坯表面发射率的测量研究[J]. 光学学报, 2016, 36(4): 0412001. Wang Peng, Xie Zhi, Hu Zhenwei. Research on Measurement of the Surface Emissivity of Casting Billets[J]. Acta Optica Sinica, 2016, 36(4): 0412001.