Engineering

What are some of the reasons why plastic shaping processes are important?

EXPERT ANSWER The reasons include (1) many of the processes are net shape processes. (2) in general, less energy is employed than in metalworking processes. (3) lower temperatures are required to process plastics than metals or ceramics . (4) there is great flexibility in geometry and (5) painting and other finishing processes are generally not …

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Annealed low-carbon steel has a flow curve with strength coefficient = 75,000 lb/in2 and strain-hardening exponent = 0.25. A tensile test specimen with gage length = 2.0 in is stretched to a length = 3.3 in. Determine the flow stress and average flow stress that the metal experienced during this deformation.

Annealed low-carbon steel has a flow curve with strength coefficient = 75,000 lb/in2 and strain-hardening exponent = 0.25. A tensile test specimen with gage length = 2.0 in is stretched to a length = 3.3 in. Determine the flow stress and average flow stress that the metal experienced during this deformation. Flow stress = Enter …

Annealed low-carbon steel has a flow curve with strength coefficient = 75,000 lb/in2 and strain-hardening exponent = 0.25. A tensile test specimen with gage length = 2.0 in is stretched to a length = 3.3 in. Determine the flow stress and average flow stress that the metal experienced during this deformation. Read More »

The stresses and strains in metal forming are of which type? elastic O plastic ultimate O fracture none of these The applied stresses in most bulk deformation processes are shear tensile O compressive O bending none of these What is the difference between the physical shape of bulk deformation and sheet metalworking manufacturing processes? In bulk deformation, the work parts have a _ area-to-volume ratio, whereas in sheet metalworking, the area-to-volume ratio is O low, high O high , low O high, high O low, low _ is a bulk deformation process in which a workpiece is compressed between two opposing dies, so that the die shapes are imparted to the work O rolling O forging O drawing extrusions O none of these _ is a compression bulk deformation process in which the work material is forced to flow through a die orifice, thereby forcing its cross section to assume the profile of the orifice O forging extrusion O drawing O extending O rolling none of these is a bulk deformation process in which the diameter of a round wire is reduced by pulling it through a die opening of smaller diameter than the wire O forging O rolling O ring rolling O ring piercing O wire lifting extrusion none of these

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A resistance spot-welding operation performed on two pieces of 2.5 mm thick sheet steel uses 12,000 amps for a 0.20 s duration. The electrodes are 6 mm in diameter at the contacting surfaces. Resistance is assumed to be 0.0001  and the resulting weld nugget is 6 mm in diameter and averages 3 mm in thickness. The unit melting energy for the metal Um = 12.0 J/mm3. What portion of the heat generated was used to form the weld nugget, and what portion was dissipated into the work metal, electrodes, and surrounding air?

A resistance spot-welding operation performed on two pieces of 2.5 mm thick sheet steel uses 12,000 amps for a 0.20 s duration. The electrodes are 6 mm in diameter at the contacting surfaces. Resistance is assumed to be 0.0001  and the resulting weld nugget is 6 mm in diameter and averages 3 mm in …

A resistance spot-welding operation performed on two pieces of 2.5 mm thick sheet steel uses 12,000 amps for a 0.20 s duration. The electrodes are 6 mm in diameter at the contacting surfaces. Resistance is assumed to be 0.0001  and the resulting weld nugget is 6 mm in diameter and averages 3 mm in thickness. The unit melting energy for the metal Um = 12.0 J/mm3. What portion of the heat generated was used to form the weld nugget, and what portion was dissipated into the work metal, electrodes, and surrounding air? Read More »

3 (a) Discuss the advantages and disadvantages of welding compared to other types of assembly operations? ​​​​​​​3 (b) Explain the three main Rapid Prototyping Process. Discuss the advantage and limitation of each process.

3 (a) Discuss the advantages and disadvantages of welding compared to other types of assembly operations?​​​​​​​3(b) Explain the three main Rapid Prototyping Process. Discuss the advantage and limitation of each process. EXPERT ANSWER 3. a) Merits and demerits of welding Merits As no hole is required for welding, hence no reduction of area. So structural …

3 (a) Discuss the advantages and disadvantages of welding compared to other types of assembly operations? ​​​​​​​3 (b) Explain the three main Rapid Prototyping Process. Discuss the advantage and limitation of each process. Read More »