EBK MANUFACTURING PROCESSES FOR ENGINEE
6th Edition
ISBN: 9780134425115
Author: Schmid
Publisher: YUZU
expand_more
expand_more
format_list_bulleted
Concept explainers
Videos
Question
Chapter 4, Problem 4.12Q
To determine
The coefficient of friction in hot working is higher than the cold working.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
Explain why friction is undesirable in metal forming operations.
A spool of wire has a starting diameter of 2.5 mm. It is drawn through a die with an opening that is 2.1 mm at a speed of 0.3 m/s. The worked metal has a strength coefficient of 450 MPa and a strain-hardening coefficient of 0.26. Assume the drawing is performed at room temperature and that the frictional and redundant work together constitute 35% of the ideal work of deformation.
Calculate the power required to carry out the operation
The figure below shows a symmetric plane-strain upsetting process. The process may also be thought of as a form of side extrusion. Observations show that the deformation is confined to two shear planes, each one being analogous to that seen in plane-strain cutting. You may assume that there is no friction between the work material and the tool/die walls; the uniaxial yield strength of the material is σy and is independent of strain rate and temperature, and the material behaves as a rigid plastic solid.
a) Calculate the pressure (p) required for the upsetting process in terms of σy.
b) If friction existed at the die walls and the frictional work (energy) dissipation was 30% of the energy required for shape change alone (part (a) above), then what would be the pressure (p)?
Chapter 4 Solutions
EBK MANUFACTURING PROCESSES FOR ENGINEE
Ch. 4 - Prob. 4.1QCh. 4 - Prob. 4.2QCh. 4 - Prob. 4.3QCh. 4 - Prob. 4.4QCh. 4 - Prob. 4.5QCh. 4 - Prob. 4.6QCh. 4 - Prob. 4.7QCh. 4 - Prob. 4.8QCh. 4 - Prob. 4.9QCh. 4 - Prob. 4.10Q
Ch. 4 - Prob. 4.11QCh. 4 - Prob. 4.12QCh. 4 - Prob. 4.13QCh. 4 - Prob. 4.14QCh. 4 - Prob. 4.15QCh. 4 - Prob. 4.16QCh. 4 - Prob. 4.17QCh. 4 - Prob. 4.18QCh. 4 - Prob. 4.19QCh. 4 - Prob. 4.20QCh. 4 - Prob. 4.21QCh. 4 - Prob. 4.22QCh. 4 - Prob. 4.23QCh. 4 - Prob. 4.24QCh. 4 - Prob. 4.25QCh. 4 - Prob. 4.26QCh. 4 - Prob. 4.27QCh. 4 - Prob. 4.28QCh. 4 - Prob. 4.29QCh. 4 - Prob. 4.30QCh. 4 - Prob. 4.31QCh. 4 - Prob. 4.32QCh. 4 - Prob. 4.33QCh. 4 - Prob. 4.34QCh. 4 - Prob. 4.35QCh. 4 - Prob. 4.36QCh. 4 - Prob. 4.37QCh. 4 - Prob. 4.38QCh. 4 - Prob. 4.39QCh. 4 - Prob. 4.40QCh. 4 - Prob. 4.41QCh. 4 - Prob. 4.42QCh. 4 - Prob. 4.43QCh. 4 - Prob. 4.44QCh. 4 - Prob. 4.45QCh. 4 - Prob. 4.46QCh. 4 - Prob. 4.47QCh. 4 - Prob. 4.48QCh. 4 - Prob. 4.49QCh. 4 - Prob. 4.50QCh. 4 - Prob. 4.51QCh. 4 - Prob. 4.52QCh. 4 - Prob. 4.53QCh. 4 - Prob. 4.54QCh. 4 - Prob. 4.55QCh. 4 - Prob. 4.56QCh. 4 - Prob. 4.57PCh. 4 - Prob. 4.58PCh. 4 - Prob. 4.59PCh. 4 - Prob. 4.60PCh. 4 - Prob. 4.61PCh. 4 - Prob. 4.62PCh. 4 - Prob. 4.63PCh. 4 - Prob. 4.64PCh. 4 - Prob. 4.65PCh. 4 - Prob. 4.66PCh. 4 - Prob. 4.67PCh. 4 - Prob. 4.68PCh. 4 - Prob. 4.69PCh. 4 - Prob. 4.70PCh. 4 - Prob. 4.71P
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, mechanical-engineering and related others by exploring similar questions and additional content below.Similar questions
- (c) A flat rolling operation is being carried out where the roll radius is 200 mm and the roll rotates at 100 rpm. The workpiece material is annealed low carbon steel with 200 mm wide and 10 mm thickness. The strength coefficient and the strain hardening of the carbon steel are 530 MPa and 0.26, respectively. The coefficient of friction is 0.2. (i) Caicurae tne roll force and torque if the workpiece is rolled to a thickness of 4 mm. (ii) Calculate the maximum possible draft and evaluate how friction effect the thickness of the rolled workpiece.arrow_forward5) A steel specimen of rectangular cross section with 120 mm width, 180 mm thickness and 90 mm height was upset at room temperature by open-die forging to a height of 55 mm. If the strength coefficient and strain hardening exponent of this material were 1015 MPa and 0.17 respectively, the coefficient of friction is 0.2, and assuming that the thickness would not change during forging; determine the required upsetting force at the end of stroke.arrow_forwardWhy is friction generally undesirable in metal forming operations?arrow_forward
- An open die forging operation is performed to produce a steel cylinder with a diameter of 9.7mm and a height of 1.7mm. The strength coefficient for this steel is 500MPA, and the strain hardening exponent is 0.25. Coefficient of friction at the die-work interface is 0.12. The initial stock of raw material has a diameter of 5mm. (a) What height/length of stock is needed to provide sufficient volume of material for this forging operation? (b) Compute the maximum force that the punch must apply to form the head in this open- die operation.arrow_forwardA blank workpiece with 200 mm diameter is to be blanked from 3.2- mm-thick half-hard stainless steel (ultimate tensile strength of 650 MPa). Find (a) the diameters of blank die and punch, and (b) blanking force.arrow_forwardAn austenitic stainless steel plate with a width of 100 mm, a length of 150 mm and a thickness of 50 mm is to be hot forged in a hydraulic press so that the width remains constant. If it is to be reduced in one step to a thickness of 40 mm, calculatea) the actual load that needs to be applied at the end of the forging, as well as b) the corresponding deformation energy. In previous plane strain compression tests, it was found that the material exhibits an average plane strain yield stress of 80 MPa at the forging temperature. Assume that the efficiency of the process is 0.6 Answer: Pfr= 2.5 MN ; WTr= 25 kJarrow_forward
- A spool of copper wire has a starting diameter of 2.5 mm. It is drawn through a die with an opening that is 2.1 mm. The entrance angle of the die = 18°. Coefficient of friction at the work die interface is 0.08. The pure copper has a strength coefficient = 300 MPa and a strain hardening coefficient = 0.50. The operation is performed at room temperature. Determine (a) area reduction, (b) draw stress, and (c) draw force required for the operation.arrow_forwardA cylindrical billet that is 100 mm long and 50 mm in diameter is reduced by indirect (backward) extrusion to a 20 mm diameter. The die angle is 90°. In the Johnson equation, a = 0.8 and b = 1.4. In the flow curve for the work metal, the strength coefficient = 800 MPa and strain hardening exponent = 0.13. Determine d) ram pressure, and (e) ram forcearrow_forward* A cylindrical workpiece made of 1100-0 Aluminum that is 18 in high and 16 in in diameter and is to be reduced in height by 25% by open-die forging. Let the coefficient of friction be 0.15. K=20 mpa,n=0.35, Calculate the forging force.arrow_forward
- One way to define forging procedures is by the extent to which the work is constrained in the die. Explain this classification system by identifying the three primary classes.arrow_forwardA cylindrical part is warm upset forged in an open die. The initial diameter is 50 mm and the initial height is 40 mm. The height after forging is 30 mm. The coefficient of friction at the die-work interface is 0.25. The yield strength of the work material is 285 MPa, and its flow curve is defined by a strength coefficient of 600 MPa and a strain-hardening exponent of 0.12. Calculate the strain at yield point.arrow_forwardWould you kindly answer this question A rolling operation on a 250 mm wide, 8 mm thick, 1112 cold rolled steel takes place using hardened steel rolls with a surface finish of 0.03 μm. The rolls have a diameter of 350 mm and rotates at 115 rpm. The final thickness of the plate is 6 mm and the entry speed of the plate is 1.8 m/s. Calculate: 3.1 The minimum coefficient of friction required, that will make the rolling operation possible. 3.2 The required roll force. 3.3 The position of the neutral point, ?? 3.4 Indicate, using a sketch, the neutral point showing all relevant notation and dimensions.arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Elements Of ElectromagneticsMechanical EngineeringISBN:9780190698614Author:Sadiku, Matthew N. O.Publisher:Oxford University Press
Mechanics of Materials (10th Edition)Mechanical EngineeringISBN:9780134319650Author:Russell C. HibbelerPublisher:PEARSON
Thermodynamics: An Engineering ApproachMechanical EngineeringISBN:9781259822674Author:Yunus A. Cengel Dr., Michael A. BolesPublisher:McGraw-Hill Education
Control Systems EngineeringMechanical EngineeringISBN:9781118170519Author:Norman S. NisePublisher:WILEY
Mechanics of Materials (MindTap Course List)Mechanical EngineeringISBN:9781337093347Author:Barry J. Goodno, James M. GerePublisher:Cengage Learning
Engineering Mechanics: StaticsMechanical EngineeringISBN:9781118807330Author:James L. Meriam, L. G. Kraige, J. N. BoltonPublisher:WILEY
Elements Of Electromagnetics
Mechanical Engineering
ISBN:9780190698614
Author:Sadiku, Matthew N. O.
Publisher:Oxford University Press
Mechanics of Materials (10th Edition)
Mechanical Engineering
ISBN:9780134319650
Author:Russell C. Hibbeler
Publisher:PEARSON
Thermodynamics: An Engineering Approach
Mechanical Engineering
ISBN:9781259822674
Author:Yunus A. Cengel Dr., Michael A. Boles
Publisher:McGraw-Hill Education
Control Systems Engineering
Mechanical Engineering
ISBN:9781118170519
Author:Norman S. Nise
Publisher:WILEY
Mechanics of Materials (MindTap Course List)
Mechanical Engineering
ISBN:9781337093347
Author:Barry J. Goodno, James M. Gere
Publisher:Cengage Learning
Engineering Mechanics: Statics
Mechanical Engineering
ISBN:9781118807330
Author:James L. Meriam, L. G. Kraige, J. N. Bolton
Publisher:WILEY
Types of Manufacturing Process | Manufacturing Processes; Author: Magic Marks;https://www.youtube.com/watch?v=koULXptaBTs;License: Standard Youtube License