ML3404 Heat Treatment of Metals and Alloys Syllabus:
ML3404 Heat Treatment of Metals and Alloys Syllabus – Anna University Regulation 2021
COURSE OBJECTIVES:
The main learning objective of this course is to prepare students for:
1. Having necessary background to design/select the necessary heat treatment for attaining the appropriate microstructure for the desired properties.
2. Getting a comprehensive understanding of the various transformation reactions associated with the changes in microstructures and properties that occur due to controlled heat treatment.
3. Understanding different case hardening techniques used in industries
4. Distinguishing the various Heat treatment furnaces, Quenching media and the heat treatment of some special alloys.
5. Getting an insight on the heat treatments employed for special alloys
UNIT I TRANSFORMATIONS IN STEELS
Allotropic changes in Iron, Iron-Iron carbide equilibrium diagram – transformations on heating and cooling – influence of alloying elements – general principles of heat treatment of steels – isothermal and continuous cooling transformations in steels – Time-Temperature-Transformation curves (TTTdiagrams), continuous cooling transformations – CCT-diagrams– effect of alloying additions on TTT diagrams, mechanism and kinetics of pearlitic, bainitic and martensitic transformations – habit plane – Bain distortion model
UNIT II HEAT TREATMENT PROCESSES
Annealing- Types, Normalising, Hardening & Quenching –Mechanisms-hardenability studies– Jominy end-quench test, Grossman’s experiments, tempering – Hollomon& Jaffe tempering correlations, retained austenite, tempering – Stages – effects of alloying elements on tempering, austempering and martempering, precipitation hardening, thermo-mechanical treatment, intercritical heat treatment, sub-zero treatment – cryogenic quenching, patenting
UNIT III CASE HARDENING
Introduction, carburisation – principle – carbon potential – mechanism – application of Fick’s law– depth of carburisation and its control – methods of carburising – heat treatment after carburizing – structure, properties and defects in carburising, nitriding – mechanism –- effect of microstructure – nitriding methods, ion-nitriding and nitro-carburising, boronising, chromising, cyaniding and carbonitriding, induction and flame hardening, Laser and Electron beam welding – principles – methods – operating variables, measurement of case depth.
UNIT IV FURNACES, ATMOSPHERE AND PROCESS CONTROL
Various heating atmosphere used for heat treatment, temperature and atmosphere control– carburising atmosphere and carbon potential measurement, Temperature Measurement Control devices – Nitriding gas atmospheres, quenching media and their characteristics, Stages of Quenching, polymer quenching, Various Heat Treatment furnaces- Roller and Mesh type continuous furnaces- fluidised bed furnaces, cryo-chamber, cryo-treatment of steels, sealed quench furnace, Vacuum furnace, Plasma equipment-Elements of Process control systems-PLC, PID controllers and continuous monitoring systems.
UNIT V HEAT TREATMENT OF SPECIFIC ALLOYS
Heat treatment of special purpose steels – tool steels, high speed steels, maraging steels, HSLA steels and die steels, heat treatment of cast irons – gray cast irons, white cast irons and S.G. irons, austempering of S.G. Iron, heat treatment of non-ferrous alloys – aluminium alloys, copper alloys, nickel alloys and titanium alloys, defects in heat treated parts – causes and remedies.
TOTAL: 45 PERIODS
COURSE OUTCOMES:
Upon completion of this course, the students will be able to:
1. Discuss the various transformation reactions associated with the changes in microstructures and properties that occur due to controlled heat treatment.
2. Explain the various heat treatment processes that can be applied for different ferrous and non-ferrous alloys.
3. Analyse the effect of various case hardening treatments on the metals and alloys.
4. Compare the various heat treatment furnaces, quenching media and furnace atmospheres.
5. Interpret the results of heat treatments on the various other non-ferrous materials, alloy steels and cast irons.
TEXT BOOKS:
1. Rajan, T. V., Sharma, C. P., Ashok Sharma., “Heat Treatment Principles and Techniques” Prentice-Hall of India Pvt. Ltd., New Delhi, 2011
2. Vijendra Singh, “Heat Treatment of Metals”, Second edition, Standard Publishers Distributors New Delhi, 2012.
REFERENCES:
1. ASM Hand book “Heat Treating”, Vol.4., ASM International, 1999.
2. I. Novikov, “Theory of Heat Treatment of Metals”, MIR Publishers, Moscow, 1978
3. Prabhudev. K. H. “Handbook of Heat Treatment of Steels”, Tata McGraw-Hill, Publishing Co., New Delhi, 1988.
4. Sydney H. Avner, “Introduction to Physical Metallurgy”, Tata McGraw Hill, New Delhi, 1997.