All Matches

Solution Library

Expert Answer

Textbooks

Search Textbook questions, tutors and Books

Oops, something went wrong!

Change your search query and then try again

Result Not Found

Books FREE
Tutors
Study Help
Hire a Tutor
AI Study Help New

Search
Sign In
Register

study help
engineering
mechanical engineering

Questions and Answers of Mechanical Engineering

Assume that the energy cost for grinding an aluminum part is $0.90 per piece. Letting the specific energy requirement for this material be 8 Ws/mm3, what would be the energy cost if the workpiece
Derive an expression for the angular velocity of the wafer as a function of the radius and angular velocity of the pad in chemical mechanical polishing?
A 25-mm-thick copper plate is being machined by wire EDM. The wire moves at a speed of 1.5 m/min and the kerf width is 1.5 mm. Calculate the power required? (Assume that it takes 1550 J to melt 1
Explain the factors involved in selecting the appropriate type of abrasive for a particular grinding operation?
An 8-in.-diameter grinding wheel, 1 in. wide, is used in a surface grinding operation performed on a flat piece of heat-treated 4340 steel. The wheel is rotating with a surface speed V = 5,000 fpm,
A 150-mm-diameter tool steel (μ = 60 W-s/mm3) work roll for a metal rolling operation is being ground using a 250-mm-diameter, 75-mm-wide Type 1 grinding wheel. The work roll rotates at 10 rpm.
Assume that you are an instructor covering the topics in this chapter, and you are giving a quiz on the quantitative aspects to test the understanding of the students. Prepare three quantitative
With appropriate sketches, describe the principles of various fixturing methods and devices that can be used for each of the processes described in this chapter?
As also described in Section 9.4, surface finish can be an important consideration in the design of products. Describe as many parameters as you can that could affect the final surface finish in
Describe how the design and geometry of the workpiece affect the selection of an appropriate shape and type of a grinding wheel?
Prepare a comprehensive table of the capabilities of abrasive machining processes, including the shapes of parts ground, types of machines involved, typical maximum and minimum workpiece dimensions,
What are the effects of wear flat on the grinding operation? Are there similarities to the effects of flank wear in metal cutting? Explain.
How would you produce a thin circular disk with a thickness that decreases linearly from the center outward?
Marking surfaces of manufactured parts with letters and numbers can be done not only with labels and stickers but also by various mechanical and non-mechanical means (see also Section 9.14.1). Make a
On the basis of the information given in Chapters 8 and 9, comment on the feasibility of producing a 10-mm diameter, 100-mm deep through hole in a copper alloy (a) By conventional drilling and (b)
Conduct a literature search and explain how observing the color, brightness, and shape of sparks produced in grinding can be a useful guide to identifying the type of material being ground and its
Visit a large hardware store and inspect the various grinding wheels on display. Make a note of the markings on the wheels and, based on the marking system shown in Figs. 9.4 and 9.5, comment on your
Obtain a small grinding wheel and observe its surfaces using a magnifier or a microscope, and compare with Fig. 9.6. Rub the periphery of the wheel while pressing it hard against a variety of flat
In reviewing the abrasive machining processes in this chapter it will noted that some processes use bonded abrasives while others involve loose abrasives. Make two separate lists for these two types
Based on the topics covered in Chapters 6 through 9, make a comprehensive table of holemaking processes,(a) Describe the advantages and limitations of each method,(b) Comment on the quality and
Precision engineering is a term used to describe manufacturing high-quality parts with close dimensional tolerances and good surface finish. Based on their process capabilities, make a list of
It can be seen that several of the processes de-scribed in this chapter can be employed, either singly or in combination, to produce or finish tools and dies for metalworking operations. Prepare a
Summarize the most important mechanical and bysical properties of plastics in engineering applications?
Discuss the significance of the glass-transition temperature, Tg, in engineering applications of polymers?
Calculate the elastic modulus and percentage of load supported by fibers in a composite with epoxy matrix (E = 100 GPa), with 20% fibers made?(a) High-modulus carbon and(b) Kevlar 29.
Calculate the stress in the fibers and in the matrix for Problem 10.100. Assume that the cross-sectional area is 50 mm2 and Fc = 2000 N.
Consider a composite consisting of reinforcing fibers with Ef = 300 GPa. If the allowable fiber stress is 200 MPa and the matrix strength is 50 MPa, what should be the matrix stiffness so that the
Conduct a survey of the recent technical literature and present data indicating the effects of fiber length on such mechanical properties as the strength, the elastic modulus, and impact energy of
Discuss the design considerations involved in "placing a metal beverage container with one made of plastic?
Using specific examples, discuss the design issues involved in various products made of plastics versus reinforced plastics?
Make a list of products, parts, or components at are not currently made of plastics, and offer reasons why they are not?
In order to use a steel or aluminum container hold an acidic material, such as tomato juice or sauce, the inside of the container is typically coated with a polymeric barrier. Describe the methods of
Using the information given in this chapter, develop special designs and shapes for possible new applications of composite materials?
Why does cross-linking improve the strength of polymers?
Would a composite material with a strong and stiff matrix and soft and flexible reinforcement have any practical uses? Explain.
Make a list of products for which the use of composite materials could be advantageous because of their anisotropic properties?
Name several product designs in which both specific strength and specific stiffness are important?
Describe designs and applications in which strength in the thickness direction of a composite is important?
Design and describe a test method to determine the mechanical properties of reinforced plastics in their thickness direction?
We have seen that reinforced plastics can be adversely affected by environmental factors such as humidity, chemicals, and temperature variations. Design and describe test methods to determine the
As with other materials, the mechanical properties of composites are obtained by preparing appropriate specimens and testing them. Explain what difficulties you might encounter in preparing specimens
Add a column to Table 10.1 describing the appearance of these plastics, including available colors and opaqueness?
It is possible to weave fibers in three dimensions and then to impregnate the weave with a curable resin. Describe the property differences that such materials would have as compared to laminated
Instead of having a constant cross section, it may be possible to make fibers or whiskers with a varying cross section or a fiber with a wavy surface. What advantages would such fibers have? Explain.
Describe the methods by which optical properties of polymers can be altered?
Polymers (either plain or reinforced) can be a suitable material for dies in sheet-metal forming operations described in Chapter 7. Describe your thoughts, considering die geometry and any other
For ease of sorting for recycling, all plastic products are now identified with a triangular symbol with a single-digit number at its center and two or more letters under it. Explain what these
Obtain different kinds of toothpaste tubes and carefully cut them across with a sharp razor blade. Comment on your observations regarding the type of materials used and how the tube could be produced?
Design a machine that uses rapid-prototyping: technologies to produce ice sculptures. Describe basic features, commenting on the effect of size a shape complexity on your design?
Explain the reasons that elastomers were developed. Based on the contents of this chapter, are there any substitutes for elastomers? Explain.
Give several examples of plastic products or components for which creep and stress relaxation would be important considerations?
Describe your opinions regarding recycling of plastics versus developing plastics that are biodegradable?
Explain how you would go about determining the hardness of the plastics described in this chapter. Would there be any significant difficulties involved? Explain.
Distinguish between composites and alloys? Give several examples.
Describe the functions of the matrix and the reinforcing fibers in reinforced plastics. What fundamental differences are there in the characteristics of the two materials?
What products have you personally seen that are made of reinforced plastics? How can you tell that they are reinforced?
What are the major differences between the properties of plastics and of metals?
Referring to earlier chapters, identify metals and alloys that have strengths comparable to those of reinforced plastics?
Compare the relative advantages and limitations of (1) Metal-matrix Composites, (2) Reinforced plastics, and (3) Ceramic-matrix Composites?
This chapter has described the numerous advantages of composite materials. What limitations or disadvantages do these materials have? What suggestions would you make to overcome these limitations?
A hybrid composite is defined as a composite material containing two or more different types of reinforcing fibers. What advantages would such a composite have over other composites?
Why are fibers capable of supporting a major portion of the load in composite materials? Explain.
Assume that you are manufacturing a product in which all the gears are made of metal. A salesperson visits you and asks you to consider replacing some of the metal gears with plastic ones. Prepare a
Review the three curves in Fig. 10.8 and describe some applications for each type of behavior. Explain your choices?
The curves given in Fig. 10.10.Review the three curves in Fig. 10.8 and describe some applications for each type of behavior. Explain your choices?
Do you think that honeycomb structures could be used in any of the components of passenger cars? If so, which components? Explain.
Other than those described in this chapter, what materials can you think of that can be regarded as composite materials? Explain.
What properties are influenced by the degree of polymerization? Explain.
What applications for composite materials can you think of in which high thermal conductivity would be desirable? Explain.
Conduct a survey of a variety of sports equipment and identify the components that are made of composite materials. Explain the reasons for and advantages of using composites for these specific
Several material combinations and structures have been described in this chapter. In relative terms, identify those that would be suitable for applications involving one of the following: (a) Very
Explain how you would go about determining the hardness of the reinforced plastics and composite materials described in this chapter. What type of tests would you use? Are hardness measurements for
Describe the advantages of applying traditional metalworking techniques covered in the preceding chapters to the forming and shaping of plastics?
Describe the advantages of cold forming of plastics over other methods of processing?
Explain the reasons that some forming and shaping processes are more suitable for certain plastics than for others?
Would you use thermosetting plastics in injection molding? Explain.
By inspecting plastic containers, such as for baby powder, you can see that the lettering on them is raised and not sunk. Offer an explanation as to why they are molded in that way?
Give examples of several parts that are suitable for insert molding. How would you manufacture these parts if insert molding were not available?
Give applications for which flammability of plastics would be a major concern in their various applications?
What manufacturing considerations are involved in making a metal beverage container versus a plastic one? Explain.
Inspect several electrical components, such as light switches, outlets, and circuit breakers, and describe the process or processes used in making them?
Inspect several similar products that are made of metals and plastics, such as a metal bucket and a plastic bucket of similar shape and size. Comment, for example, on their respective thicknesses,
Make a list of processing methods used for reinforced plastics. Identify which of the following fiber orientation and arrangement capabilities each has: (1) Uniaxial, (2) Cross-ply, (3) In-plane
As you may have observed, some plastic products have lids with integral hinges; that is, no other material or part is used at the junction of the two parts. Identify such products and describe a
Explain why some shaping operations, such as blow molding and film-bag making, are done vertically and why buildings that house equipment for these operations have ceilings 10 to 15 m (35 to 50 ft)
Consider the case of a coffee mug being produced by rapid prototyping. Describe how the top of the handle can be manufactured, since there is no material directly beneath the arch of the handle?
Make a list of the advantages and disadvantages of each of the rapid-prototyping operations?
Explain why finishing operations are generally needed for rapid-prototyping operations. If you are making a prototype of a toy car, list the finishing operations you would want to perform?
A continuing topic of research involves producing parts from rapid-prototyping operations and then using them in experimental stress analysis in order to infer the strength of the final parts
What properties do elastomers have that thermo plastics, in general, do not have?
Because of relief of residual stresses during curing, long unsupported overhangs in parts made by stereolithography will tend to curl. Suggest methods of controlling or eliminating this problem?
One of the major advantages of stereolithography and cyberjet is that semi- and fully-transparent polymers can be used, so that internal details of parts can readily be discerned. List parts or
Based on the processes used to make fibers, as described in this chapter, explain how you would produce carbon foam. How would you produce metal foam?
Die swell in extrusion is radially uniform for circular cross sections but is not uniform for other cross sections. Recognizing this fact, make a qualitative sketch of a die profile that will
What are the advantages of using whiskers as a reinforcing material? Are there any limitations?
By incorporating small amounts of blowing agent, it is possible to produce polymer fibers with gas cores. List some applications for such fibers?
With injection-molding operations, it is common practice to remove the part from its runner and then to place the runner into a shredder and recycle into pellets. List the concerns you would have in
What characteristics make polymers attractive for applications such as gears? What characteristics would be drawbacks for such applications?
Can polymers be made to conduct electricity? Explain, giving several examples.
Why is there so much variation in the stiffness of various polymers? What is its engineering significance? Explain, with examples.

Showing 17400 - 17500 of 18208

First
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
Last

Services

Sitemap
Fun
Definitions
Become Tutor
Study Help Categories
Recent Questions
Expert Questions

Company Info

Security
Copyrights
Privacy Policy
Terms & Conditions
SolutionInn Fee
Scholarship

Get In Touch

About Us
Contact Us
Career
Jobs
FAQ
Campus Ambassador

Secure Payment

Download Our App

© 2024 SolutionInn. All Rights Reserved