Materials Engineering (MCEN90014)
TC Practice Workshops
1. Gibbs free energy of a thermodynamic system helps to calculate several thermodynamic parameters. Given the Gibbs free energy function (G), drive equations for calculation of volume, entropy, enthalpy, internal energy of a thermodynamic system.
2. Calculate the phase diagram of Iron-Carbon binary alloy i.e. Temperature vs composition of carbon diagram using Thermo-Calc. Consider range of carbon from 0 to 1 wt% and the corresponding temperature range between 500 and 1800 K.
3. For the phase diagram calculated in Q2, add 5 wt % Cr and re-calculate and plot the new phase diagram (Temp vs conc of carbon). Compare and contrast the results for Q2 and Q3.
4. Calculate the phase diagram for Al-Si alloy. Consider a temperature range of 200 to 700C and vary composition silicon from 0 to 10 wt%.
Ø Identify the appropriate thermodynamic database
Ø Indicate/label the different phase region
Ø What is the maximum composition of Si for austenite (FCC) Al-Si alloy
5. Calculate the Cu-Sn binary phase diagram. Consider a temperature range of 500 to 1200C.
Ø Identify the appropriate thermodynamic database
Ø Indicate/label the different phase region
Ø Estimate the melting point of Cu-38 wt% Sn alloy
6. Calculate the Cu-Ni binary phase diagram. Consider a temperature range of 1000 to 1500C.
Ø Identify the appropriate thermodynamic database(s)
Ø Identify the liquidus and solidus lines.
Ø Indicate/label the different phase regions
Ø Calculate the phase fraction at 1232C for an alloy of Cu-38wt%Ni and compare the result with the one obtained from lever rule. Use data from TC for Lever rule.
7. Plot the phase fraction of an Fe-0.25 wt % C alloy as a function of temperature. Consider temperature range of [800 to 1400C].
8. Using the Fe-C system, generate the equilibrium phase diagram for the composition range 0 - 6 wt% C and temperature range 300 - 1600 °C (new).
Ø Identify the eutectoid and eutectic points.
Ø At 0.8 wt% C and 727 °C, what phases are present?
Ø What is the phase fraction of graphite at 4.4 wt% C and 1147 °C?
9. Determine the phase compositions for an Iron-Carbon binary alloy (C = 3 wt%) at 1200K. Also determine the Enthalpy and total Gibbs energy of the alloy at 1200K.
10. Set the composition to Fe - 18Cr - 0.8C (wt%) and calculate equilibrium phases at 1200 °C (new).
Ø Which phases are stable at this condition?
Ø How does the phase fraction of carbide change when temperature is decreased to 900 °C?
Ø At what temperature does sigma phase first appear?
11. Perform. a single point equilibrium calculation using Thermo-Calc for an Fe-C binary alloy at C = 2.5 wt% and T = 1500K.
Ø Determine the stable phases at 1500K
Ø Determine the fraction of stable phases at 1500K.
12. Fix composition: Fe–30Ni–0.5C (wt%). Calculate equilibrium at 600 °C and 1000 °C (new).
Ø What are the stable phases at both temperatures?
Ø How does the amount of austenite vary?
Ø Which phase(s) dissolve/disappear when going from 600 °C to 1000 °C?
13. Calculate the phase diagram of Cr-Ni binary alloy (Temperature vs composition of Nickle) using Thermo-Calc.
Ø Consider composition of Ni from 0 to 100% by wt and the temperature range between 1000 and 2000 K.
Ø Designate the respective phases in each of the areas in the phase diagram.
Ø Compare the phase diagram that you find from Thermo-calc with that from literature (you may search from internet using the key words ‘Cr-Ni binary alloy phase diagram’).
Ø Calculate the fraction of phases as a function of temperature for a binary alloy containing 50 wt% of Cr.
14. Calculate and provide phase diagram of Fe-Cr binary alloy between T = 1000 and 2000K. Consider composition of Cr between 0 to 30 wt%.
Ø Indicate the different phases on the phase diagram
15. Use single point equilibrium calculations for an alloy (with composition of elements provided in the Table 1) to determine the phase fraction of face centered cubic structure (FCC_A1) at 1600K.
Table 1: composition of alloy
|
Element
|
Fe
|
Ni
|
C
|
|
%wt
|
Bal
|
12
|
0.02
|
16. Use the Property model in Thermo-Calc to calculate and plot the increase in yield strength of Fe-C alloy as a function of concentration of carbon due to solution hardening. Consider the concentration of carbon increases from 0 to 1wt %.
17. WC-Co system is mainly used for cutting other materials due to its superior hardness and fracture resistance. It is produced by mixing powder particles of WC and 10wt% Co and sintering (heat treating) them at high temperatures. The process (sintering) requires microstructural phases consisting of FCC, MC_SHP and LIQUID phases co-existing together at equilibrium. Determine the window of temperature and carbon concentration in which you can produce WC-Co cutting tools. [Hint: For this problem, you may have to use the licensed version of TC available on GPU desktops that can be accessed through myUniApps].
18. Al-Cu alloys are commonly used in the aerospace industry due to their high strength and can be precipitation harden-able but they suffer from casting issues. Si is often added to improve the castability. Calculate the phase diagram for Al-Cu alloy. Consider a temperature range of 200 to 1100C and vary copper composition from 0 to 60 wt%.
Ø Identify the appropriate thermodynamic database
Ø Indicate/label the different phase region
Ø What is the maximum composition of Cu for austenite (FCC) Al-Cu alloy
o At what temperature does this composition exist?
Ø Using a grid based analysis, determine the maximum composition of Si that can be added to the Al-Cu alloy to retain the austenite region for precipitation hardening.
Ø Add a “Property Model Calculator” into the tree connecting to the previous “System Definer” and “Plot Renderer” and determine the total yield strength based on precipitation hardening and overlay it on the grid based analysis.
19. Compare and contrast the stable as well as metastable phase diagrams of an Fe-C system. Consider composition of carbon varying from 0 to 0.3 wt % and temperature from 500 2000C (new)
20. Composites of Silica and Alumna are used in various industries, including high-temperature applications like aerospace and as a component in coatings for enhanced thermal shock resistance. Calculate the binary phase diagram of Silia and Alumna composites (SiO2 - Al2O3). Consider varying the mole fraction of Alumna (Al2O3) from 0 to 1 with temperature range of 1200 to 2500K (new).
Ø Discuss and identify the relevant thermodynamic database.
Ø Discuss how to incorporate the oxides as opposed to the metallic elements.
Ø Plot phase diagram and label the different ceramic phases.
Ø Compare the calculated phase diagram with that of an experimentally determined phase diagram. Find an experimentally determined phase diagram of SiO2 – Al2O3 in ‘Week 6 - Intro to phase diagrams - L1’. Discuss the difference.
Ø Hint: Follow the TC tutorial >> https://www.youtube.com/watch?v=donmXmxsjvo&list=PLfv6McToaTGSzHrh3TfNF2EhoUUUqeEWd&index=13