show the correlation between weight percent carbon, volume percent pearlite, and tensile strength for hot rolled carbon
steels by
1- Looking up the tensile strengths in psi for the following hot rolled AISI carbon steels in matweb.com: 1006, 1010,
1020, 1025, 1030, 1035, 1040, 1045, 1050, 1055, 1060, 1065, and 1070.
2- Calculating the volume percent pearlite for each steel (assume that vol.% pearlite = wt.% pearlite) using the lever
rule and the nominal carbon content indicated by the AISI number.
3- Recording the values in an EXCEL Worksheet that has columns for wt. %C, vol.% pearlite, and tensile strength.
4- Plotting EXCEL graphs of vol.% pearlite versus wt. %C, tensile strength versus wt. %C, and tensile strength
versus vol.% pearlite
In: Mechanical Engineering
In: Mechanical Engineering
In: Mechanical Engineering
1. A black thermocouple measures the temperature in a chamber with black walls. If the air around the thermocouple is at 20°C, the walls are at 100°C, and the heat transfer coefficient between the thermocouple and the air is 15 W /m2·°C, what temperature will the thermocouple read
In: Mechanical Engineering
3. A stainless steel sphere of thermal conductivity 16 W/m · K with a diameter of 4 cm is exposed to a convective environment of 15 W/m2 · K, 20?C. Heat is generated uniformly in the sphere at a rate of 1.0 MW/m3 . Determine the steady-state temperature of the sphere at its center and its surface. Also determine the heat flux at a radius of 1.5 cm.
In: Mechanical Engineering
A bicycle rider is interested in the effects of temperature on air density. A change in temperature will also affect the tire pressure.
a) Write a computer program that calculates air density at atmospheric pressure for temperatures from -10?C to 50?C.
b) Assume that a bicycle tire is inflated to an absolute pressure of 450 kPa at 20?C. Assume also that the volume of the tire does not change with temperature. Write a program to show how the tire pressure changes with the temperature in the same range, -10?C to 50?C.
Prepare a table or graph or both.
In: Mechanical Engineering
Which of the following statements are true regarding AMF/3MF files, in comparison to STL files?
Select all that apply.
a) AMF/3MF files can represent overhangs of greater than 45 degrees, while STL files cannot
b) AMF/3MF files do not require the model to be sliced before printing
c) AMF files can specify multiple materials within the same part
d) The 3MF file format can enumerate the structure of a lattice as a periodic unit, making the file size more compact
In: Mechanical Engineering
In: Mechanical Engineering
In: Mechanical Engineering
A piston-cylinder assembly has initially a volume of 0.3 m3 of air at 25 oC. Mass of the air is 1 kg. Weights are put on the piston until the air reaches to 0.1 m3 and 1,000 oC, in which the air undergoes a polytropic process (PVn = const). Assume that heat loss from the cylinder, friction of piston, kinetic and potential effects are negligible. 1) Determine the polytropic constant n. 2) Determine the work transfer in kJ for this process, and discuss its direction. 3) Sketch the process in T-V (temperature-volume) diagram.
In: Mechanical Engineering
Determine the missing properties for refrigerant R134a (CF3CH2F) for each state given. Show your three step decision process: i.e. 1) list two known properties, 2) determine the phase, 3) look up/interpolate properties from the correct table and show all calculations made for each case.
| Phase/quality | T | P | v | u | h |
| Phase name/X | celcius | kPa | m^3/kg | kJ/kg | kJ/kg |
| Sat. liquid | 520 | ||||
| 10 | 0.012 | ||||
| 73 | 685 | ||||
| 375 | 120 |
In: Mechanical Engineering
PART I. For this problem you are allowed and encouraged to look for data or a problem online. What is important in here is to present the analysis.
Identify a quality control problem either in an industrial facility or in a service facility.
Define what the product or service is.
Identify the quality characteristics: dimensions and/or attributes
Identify what are the critical characteristics of your product to pay attention as a quality engineer
Create a fishbone diagram of the problem identified. Include all potential causes of your problem.
Use a Pareto Chart to help you identify the root cause.
In: Mechanical Engineering
| Select the best answer for the question. |
|
1. Which of the following statements about engine configurations is true? |
|||||||||
|
|||||||||
In: Mechanical Engineering
|
Engineer Doe is employed on a full-time basis by a radio broadcast equipment manufacturer as a sales representative. In addition, Doe performs consulting engineering services to organizations in the radio broadcast field, including analysis of their technical problems and, when required, recommendation of certain radio broadcast equipment as may be needed. Doe’s engineering reports to his clients are prepared in form for filing with the appropriate governmental body having jurisdiction over radio broadcast facilities. In some cases Doe’s engineering reports recommend the use of broadcast equipment manufactured by his employer. Can Doe ethically provide consulting services as described? What NSPE Code of Ethics references might apply to this case? |
In: Mechanical Engineering
The propeller shaft of a large ship has an outside diameter of 350 mm and inside diameter 250mm. the shaft is rated for a maximum of shear stress 62 MPa.
1) if the shaft is runnning at 500 rpm what is the maximum power that can be transmitted without exceeding allowable stress.
2) if the rotational speed of the shaft is doubled but the power requirements unchanged what happens to the shear stress in the shaft? calculate valures.
In: Mechanical Engineering