Development of an In-Process Technique for Measuring Temperatures and Micro-Geometry of High Temperature Surfaces by Using the Broad Range Spectroscopy

为了发展一种利用宽谱技术测量高温表面温度和微观形貌的在线技术，进行了一系列的工作：1。对高速分光光度计系统进行了改进，使光谱范围扩大到0.35- 14.5 μ m。采用波长连续可变滤波器.研究了几种不锈钢和高温合金在高温空气氧化过程中反射特性的瞬态行为。光谱被发现是由一些简单的规则的干扰和衍射的辐射在粗糙的氧化表面的特点.在1000 K附近的空气中，发现了一个有趣的温度滞后现象。这是由于在表面氧化和脱溶反应的联合作用.研制了一种用于测量真实的表面正入射半球反射光谱的椭球镜式反射计系统。将该系统应用于粗糙金属表面的角度和波长特性的测量.提出了一种描述粗糙金属表面反射特性的理论模型。该表面被建模为一个类似分形的三维结构，它由离散和统计控制的表面元素。计算了衍射/散射特性，验证了模型的真实性.针对实际工业环境中真实的表面反射特性的瞬态行为，提出了另一种处理方法。将上述表面模型与三维非平行膜单元模型相结合。实验发现的光谱跃迁行为在计算机的基础上很容易在理论上再现。

A series of works were performed for the development of an in-process technique for measuring temperatures and micro-geometry of high temperature surfaces by using the broad range spectroscopy :1. The high-speed spectrophotometer system was modified to extend the spectral region to 0.35-14.5mum. A wavelength continuous variable filter was used for it .2. Transient behavior in reflection characteristics was investigated on several kinds of stainless steels and super-alloys in an air-oxidation process at high temperatures. The spectra were found to be characterized by a few simple rules of interference and diffraction of radiation at the roughened oxidized surfaces.3. An interesting phenomenon of temperature hysteresis was found in the near -infrared spectra of emission and reflection at a paradium surface in air and at around 1000K. It was attributed to the combined oxidation and desociation reactions at the surface.4. An ellipsoidal mirror-type reflectometer system was developed to measure the normal-incident hemispherical reflectance spectra of real surfaces. The system was applied to the measurement of the angular and wavelength characteristics of rough metallic surfaces.5. A theoretical model was proposed to describe the reflection characteristics of rough metallic surfaces. The surface was modelled as a fractal-like three-dimensional structure which consists of discrete and statistically controlled surface elements. The diffraction/ scattering characteristics were calculated to demonstrated the reality of the model.6. Another idea was proposed to deal with the transient behavior in reflection characteristics of real surfaces in actual industrial environments. The above surface model was combined with a three-dimensional non-parallel film element model. The experimentally found behavior of the spectrum transition was readily reproduced theoretically on a basis of a computer.