Editing Thermal analysis (section)

==Metals==
Production of many metals ([[cast iron]], [[grey iron]], [[ductile iron]], [[compacted graphite iron]], [[aluminium alloy#Wrought alloys|3000 series aluminium alloys]], [[copper alloys]], [[silver]], and complex [[steel]]s) are aided by a production technique also referred to as thermal analysis.<ref>{{cite journal|last=Emadi|first=D|author2=L. V. Whiting |author3=S. Nafisi |author4=R. Ghomashchi |journal=Journal of Thermal Analysis and Calorimetry|year=2005|volume=81|issue=1|pages=235–242|doi=10.1007/s10973-005-0772-9|title=Applications of thermal analysis in quality control of solidification processes|s2cid=96442065}}</ref> A sample of liquid metal is removed from the furnace or ladle and poured into a sample cup with a thermocouple embedded in it. The temperature is then monitored, and the phase diagram arrests ([[liquidus]], [[eutectic]], and [[solidus (chemistry)|solidus]]) are noted. From this information chemical composition based on the phase diagram can be calculated, or the crystalline structure of the cast sample can be estimated especially for silicon morphology in hypo-eutectic Al-Si cast alloys.<ref>{{cite journal|last=Farahany|first=Saeed|author2=Ali Ourdjini |author3=Mohd Hasbullah Idris |title=The usage of computer-aided cooling curve thermal analysis to optimise eutectic refiner and modifier in Al–Si alloys|journal=Journal of Thermal Analysis and Calorimetry|year=2012|volume=109|issue=1|pages=105–111|doi=10.1007/s10973-011-1708-1|s2cid=138476636 }}</ref>  Strictly speaking these measurements are ''cooling curves'' and a form of sample controlled thermal analysis whereby the cooling rate of the sample is dependent on the cup material (usually bonded sand) and sample volume which is normally a constant due to the use of standard sized sample cups. To detect phase evolution and corresponding characteristic temperatures, cooling curve and its first derivative curve should be considered simultaneously. Examination of cooling and derivative curves is done by using appropriate data analysis software.  The process consists of plotting, smoothing and curve fitting as well as identifying the reaction points and characteristic parameters. This procedure is known as Computer-Aided Cooling Curve Thermal Analysis.<ref>{{cite journal | doi = 10.1007/s10973-013-3005-7 | volume=114 | issue = 2 | title=Computer-aided cooling curve thermal analysis of near eutectic Al–Si–Cu–Fe alloy | journal=Journal of Thermal Analysis and Calorimetry | pages=705–717| date = November 2013 | last1 = Shabestari | first1 = S. G. | last2 = Idris | first2 = M. H. | last3 = Ourdjini | first3 = A. | last4 = Farahany | first4 = S. | s2cid=94656052 }}</ref>

Advanced techniques use differential curves to locate endothermic inflection points such as gas holes, and shrinkage, or exothermic phases such as carbides, beta crystals, inter crystalline copper, magnesium silicide, iron phosphide's and other phases as they solidify. Detection limits seem to be around 0.01% to 0.03% of volume.

In addition, integration of the area between the zero curve and the first derivative is a measure of the specific heat of that part of the solidification which can lead to rough estimates of the percent volume of a phase. (Something has to be either known or assumed about the specific heat of the phase versus the overall specific heat.) In spite of this limitation, this method is better than estimates from two dimensional micro analysis, and a lot faster than chemical dissolution.