It is proposed to include following joining technologies of commercial importance under different groups of processes
A) Fundamentals of Metal Joining Technologies: mechanisms for obtaining metallic continuity: fusion, deformation, diffusion, chemical interactions
B) Fusion based processes: principle of fusion welding processes, oxy-fuel has welding, common arc welding processes, laser beam welding, spot welding processes, newer variants of fusion welding processes
C) Solid-liquid joining processes: brazing and soldering, braze welding, cold metal transfer welding,
D) Solid state joining processes: diffusion bonding, ultrasonic welding and explosive welding and
E) Adhesive joining: design, procedure, and applications
F) Metallurgical Aspects of Welding: weld thermal cycle, solidification of weld metal, weldability of carbon steel, alloys steel, stainless steels, and aluminium alloys, Fe-C, CCT and schaffler diagram for understanding the metallurgical transformation in weld and heat affected zone., basics of residual stresses
G) Common issues related with joining technologies their causes and remedies: hardening and softening of heat affected zone, porosity, cracking.
INTENDED AUDIENCE:
It is a core course for UG/PG students, practicing engineers.
PRE-REQUISITES:
None
INDUSTRIES THAT WILL RECOGNIZE THIS COURSE:
None
1055 students have enrolled already!!
COURSE INSTRUCTOR
Dr. D. K. Dwivedi obtained BE (mechanical engineering) , in 1993 from GEC Rewa, ME (welding engineering) Univ. of Roorkee in 1997 and PhD in Met. Engineering from MNIT, Jaipur in 2003. He has about 9 years teaching experience at NIT Hamirpur and 12 years at IIT Roorkee of subjects related with manufacturing at UG level and welding engineering related subjects at PG level. He has published more than 95 research papers in SCI/SCIE indexed journals and undertaken 16 sponsored research and 48 industrial consultancy projects. Instructor has authored one book entitled “Production and Properties of Cast Al-Si Alloys with New Age International, New Delhi (2013).
COURSE LAYOUT
Week 1: Introduction: Manufacturing and Joining Fundamental Mechanisms of joining, heat and pressure in joining Classification of joining processes,Heat generation and power density concept in welding Protection of the weld metal approaches, effect of gases on weld properties
Week 2: Principle of fusion welding processes, oxy-fuel gas welding Fundamentals of welding: type of weld, types of joint, welding position, arc heat generation Physics of welding arc: arc initiation, maintenance, shielded metal arc welding Electrode melting rate, effect of electrode polarity and welding parameters Gas tungsten arc welding: electrode, shielding gases, Introduction of gas metal arc welding
Week 3: Variants of Gas tungsten arc welding: GTAW, Hot wire GTAW, Flux assisted GTAW Variants of Gas metal arc welding: Pulse GMAW, CMT welding Submerged arc welding Electro-slag and Electro-gas welding processes Laser beam welding
Week 4: Brazing Soldering and Braze welding, Fundamentals of resistance welding Resistance welding processes: spot, seam welding Flash butt welding
Week 6: Explosive welding, Magnetic pulse welding, Weld thermal cycle, Heat affected zone and weld thermal cycle: I, Heat affected zone and weld thermal cycle: II
Week 7: Solidification of weld metal, Fundamentals of weldability of metals, Weldability of carbon & alloy steels: Fe-C, CCT, Weldability of stainless steels: schaeffler diagram, Metallurgical transformation in weld and heat affected zone of steels
Week 8: Weldability of aluminium alloys: porosity, HAZ softening, PMZ issues, Solidification cracking and their control, Residual stresses in weld joints: effect on joint performance, and control of residual stress, Cracking of welded joints: solidification and liquation cracks, Cracking of welded joint: cold cracking
SUGGESTED READING
Metals Handbook-Welding, Brazing and Soldering, American Society for Metals, 1993, 10th edition, Volume 6, USA.
Richard Little, Welding and Welding Technology, McGraw Hill, 2001, 1st edition.
H Cary, Welding Technology, Prentice Hall, 1988, 2nd edition.
S V Nadkarni, Modern Arc Welding Technology, Ador Welding Limited, 2010, New Delhi.
R S Parmar, Welding process and technology, Khanna Publisher, New Delhi
Welding handbook, American Welding Society, 1987, 8th edition, volume 1 & 2, USA
CERTIFICATION EXAM
The exam is optional for a fee.
Date and Time of Exams: April 28 (Saturday) and April 29 (Sunday) : Afternoon session: 2pm to 5pm
Exam for this course will be available in one session on both 28 and 29 April.
Registration url: Announcements will be made when the registration form is open for registrations.
The online registration form has to be filled and the certification exam fee needs to be paid. More details will be made available when the exam registration form is published.
CERTIFICATES:
Final score will be calculated as : 25% assignment score + 75% final exam score.
25% assignment score is calculated as 25% of average of best 6 out of 8 assignments.
E-Certificate will be given to those who register and write the exam and score greater than or equal to 40% final score. Certificate will have your name, photograph and the score in the final exam with the breakup. It will have the logos of NPTEL and IIT ROORKEE. It will be e-verifiable at nptel.ac.in/noc.
