MATSE 444: Welding and Joining Processes

Homepage: Lecture materials are posted on the web.

Textbook: Cary, Modern Welding Technology, 4th Ed.

References: Lancaster, The Metallurgy of Welding Brazing and Soldering

Catalog Description, Prerequisites and Schedule:

Same as CEE 375. The physical principles of fusion welding; heat flow; thermal cycles; physical metallurgy and mechanical properties of welded joints; applications of welding to large structures; testing of welds; nondestructive testing; design, economics and weld specifications; and laboratory experiments in welding. Prerequisite: TAM 226, 206 or equivalent. 3 hours or 3/4 or 1 unit. 3 hours lecture-discussion/week plus laboratory time

Course Topics:

1. Introduction: history of welding, survey of welding processes, welding terminology, welding symbols.
2. Common Industrial Welding Processes: oxyacetylene welding, shielded metal arc welding, gas tungsten arc welding, gas metal arc welding, resistance spot welding.
3. Physics of Welding: the welding arc, electrical machinery and behavior, process control, cost estimation, heat flow and temperature distributions, weld metal phenomena, contractions and residual stresses.
4. Weld Defects: weld cracking, weld defects, welding codes, contractions and residual stresses. nondestructive testing methods, radiographic nondestructive testing, ultrasonic nondestructive testing,, quality control and assurance.
5. Metallurgy of Welding: weldability of mild steel, weldability of stainless steel, weldability aluminum alloys, weldability of cast iron.
6. Mechanical Properties of Weldments: static design concepts, fracture mechanics, fracture control concepts, fatigue of welds.

Course Objectives:

1. Survey important ideas and concepts associated with welding technology.
2. Provide a bridge between the academic and real world.
3. Act as a capstone course by integrating knowledge from many areas of natural science and engineering through the wide range of issues that arise in a discussion of welding technology.
4. Provide a limited amount of experience welding.

Course Outcomes:

1. Students are familiar with all the common welding process
2. Students are familiar with all the common welding problems associated with welding ferrous materials and aluminum alloys.
3. Students are aware of factors which control the cost of welding.
4. Students are exposed to industrial welding practices and problems during a field trip to Caterpillar Decatur that concludes the course. This field trip proves to the students that all the concepts covered in the course are critical in the manufacturing of quality heavy equipment.
5. Students are exposed the static and fatigue strength of weldments - one of the most important applications of fracture mechanics and the science of metallic fatigue - in the last part of the course. The students are asked to become thoroughly familiar with and comment on one of the classical studies of the failure of welded structure at the conclusion of the course.
6. Topics such as plasma physics, heat flow, physical metallurgy, nondestructive testing, fracture mechanics, economics, industrial safety, physical chemistry, thermodynamcs, and electrical circuits arise in the course and are integrated though the importance of these topics in a rational discussion of welding.
7. Students appreciate the great skill of good welders after their attempts at welding. The students become aware of how difficult it is to make a good weld and why weld defects occur as frequently as they do.

Assessment Tools:

1. Knowledge of welding ideas tested in two hour exams and a final. Weekly quantitative homework underscores underlying physical principles.
2. Bridge between academic and real world is provided by many case studies presented in lecture.
3. The hand-on laboratory experience with welding that includes the preparation of a weldment, which is radiographed and tested to failure in tension. Grade on this laboratory assignment is based on the quality of the weld produced.
4. A thorough metallurgical study of a weldment is executed by teams of students who must cooperate and write a single, well prepared report.

Contribution of Course to Meeting the Professional Component

100%

Prepared by:

Frederick Lawrence, March 2001