熱重量分析 ---- 物質隨著環境溫度的上升或下降而改變其重量之分析謂之為熱重量分析. 例如物質在某一溫度下減少重量, 表示物質在此溫度產生蒸發或分解, 如果物質在某溫度範圍內重量沒有損失即表示該物質在此溫度範圍是呈現安定狀態. 量測物質在各不同溫度下之重量可以判斷化合物之成份及混合物中各成份之含量.

一部完整的熱重量分析應包括:

• 電氣高溫爐 ---- 能夠很穩定的升降溫度使樣品可獲得不同的溫度.
• 精密分析天枰 ---- 能連續度量試樣之重量變化.
• 記錄裝置 ---- 用以連續記錄溫度與試樣變化之狀況.

熱差分析 ---- 將樣品及參考用試樣同時以一定的速度緩慢升溫, 兩者因熱容量不同而上升溫度各異, 但二者之溫度差DT維持一定. 如果樣品因相的變化或化學反應而吸熱或放熱, 使其溫度不變或急速上升而與參考試樣不保持一定. 度量二者溫度差 (溫度降低 -- 樣品吸熱, 或溫度上升 -- 樣品放熱)隨升溫時間變化狀態稱之為熱差分析.

完備的熱差分析儀器應包含:

• 樣品及參考試樣容器, 需各具有獨立的測溫功能
• 電氣高溫爐
• 記錄裝置 ---- 用以連續記錄溫度變化之狀況.

熱膨脹分析 ---- 熱膨賬分析 Thermodilatometric Analysis (TDA) 是應用於量測物質在不同溫度下其體積變化之情形, 亦可稱之為熱機械性分析 Thermomechanical Analysis (TMA).

完整的熱膨脹分析儀器應包含:

• 樣品容器, 需具有度量樣品位移之感測裝置
• 電氣高溫爐
• 記錄裝置 ---- 用以連續記錄溫度及樣品位移之變化狀況.

Harrop's approach to thermal analysis is to make it inexpensive and reliable and keep it simple to operate. Following that philosophy. Harrop has produced a line of thermal analysis modules and complete systems that offer the best overall value -- proof that thermal analysis instrumention does not have to be expensive to be effective. Harrop's thermal analysis modules offer a wide range of standard and optional features to meet the user's individual needs. Module temperature capabilities range from -170ºC to +1,700ºC. Module sample atmospheres range from ambient to inert, reactive, or vacuum.

Thermogravimetric Analysis (TGA) measures the weight change of a test sample as the temperature rises. Points along the temperature curve which indicate rapid weight loss are useful in determining at what points along the firing curve time must be allowed to assure safe completion of these reactions. The temperatures at which the reactions occur are also indicators of the compositions involved. Changes in sample weight may be due to oxidation, decomosition, reduction, volatilization, sublimation, and reactions within the sample.

Harrop TGA modules are available in temperature ranges from room temperature to +1,700ºC, and in a variety of balance sensitivities from 100 microgram to 0.1 microgram. Atmosphere conditions range from ambient to vacuum, and inert to reative. Most modules are configured for digital output and analysis.

Differential Thermal Analysis (DTA) is a "fingerprinting" techniaue that detects heat release or heat absorption caused by the chemical and physical changes which occur within the material during heating and cooling. The point along the temperature curve at which the reaction takes place can predict which reaction look place, and the magnitude of deviation of the curve can give an idea of the relative size of the reaction. Changes in the sample which result in a release of heat (exotherm) or absorption of heat (endotherm) may be caused by such detectable phenomena as decomposition, exidation crystalline phase change, glass transition, Curie point, sintering, melting, and other chemical reactions. Both qualitative and quantitative data may be generated.

Harrop DTA Modules are available in temperature ranges from -170ºC to +1,700ºC, are designed for various atmospheres (ambient air, light vacuum to 1,500 psi, and non-corrosive gasses), and can be configured for either digital or analog output and analysis.

Thermodilatometric Analysis (TDA), often called Dilatometry or Thermomechanical Analysis (TMA), measures the dimensional changes of materials as a function of temperature change. TDA measures both reversible and irreversible changes in length of a specimen during heating and cooling, and pinpoints where reactions occur which cause sudden expansion or contraction in the material, which could result in stresses sufficient to cause cracking. TDA determinations include: Expansion Co-efficient (a), Softening Point, Glass Transition Temperature, Curie Point, Crystalline Transformation, Phase Transition, Shrinkage and Warping, Bloating, Sintering Rate, Sintering Characterization, Isothermal Creep, and Stress Relaxation.

Harrop makes dilatometers with several options: temperature ranges from -170ºC to +1,700ºC, horizontal or vertical, single, multiple, or differential, standard or large sample size, ambient or controlled atmospheres (inert, reactive, or vacuum), and digital or analog output and analysis.

其它熱分析儀器及相關產品資料請參閱  美國 ORTON PRODUCTS