Consider the gas carburizing of a gear of 1020 steel at 927°C (1700°F) as in ExampleProblem 5.2. Only in this problem calculate the carbon content at 0.50 mm beneath the sur-face of the gear after 5 h carburizing time. Assume that the carbon content of the surface ofthe gear is 0.90%, and that the steel has a nominal carbon content of 0.20%.Danin=1.28 x 10-11 m2/s1Solution

Answered: Image /qna-images/answer/10ab4750-f2e1-4168-aa44-6f6dddceae8c.jpg

Answered: Consider the gas carburizing of a gear…

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

See similar textbooks

Similar questions

Problem 2 Consider the gas carburizing of a gear 1020 steel at 927°C. Calculate the time (in minute) necessary to increase the carbon content to 0.40 wt% at 0.5 mm below the surface. Assume that the carbon content at the surface 0.9 wt% and that the steel has a nominal carbon content of 0.2 wt%. Given: Diffusivity of C in Fe at 9270C is 1.28 x 10-11 m²s-1, activation energy is 148 kJmol-1, gas constant is 8.31 Jmol-1K-1, if erf (Z) = 0.7143, Z = 0.755. %3D
To increase hardness of steel gear, it was carburized at 1040°C by introducing 1.5%C at its steel surface. What will be the final carbon content 0.0014 m beneath the surface if this treatment was lasted for 12 hours. The initial carbon content of steel is 0.1%C. (gas constant is 8.31 J/mol K).
For a steel alloy it has been determined that a carburizing heat treatment of 18 h duration at 885°C will raise the carbon concentration to 0.46 wt% at a point 2.0 mm from the surface. Estimate the time necessary to achieve the same concentration at a 8.4 mm position for an identical steel and at a carburizing temperature of 1120°C. Assume that Do is 2.5 x 10-4 m2/s and Qa is 104 kJ/mol.
A certain component is to be carburized to obtain 0.592 wt % C at a depth of 2.0 mm. After carburizing (for 1.2 hours) the heat treater finds that he achieved 0.4 wt % C at a depth of 2.0 mm His furnace only operates at a 900 *C and maintains a constant atmosphere of 1 wt % C. The steel used has an initial carbon content of 0.2 wt %. How long (in hours) should he carburize to achieve his goal?
For a steel alloy it has been determined that a carburizing heat treatment of 16 h duration at 731°C will raise the carbon concentration to 0.40 wt% at a point 3.9 mm from the surface. Estimate the time necessary to achieve the same concentration at a 7.9 mm position for an identical steel and at a carburizing temperature of 1060°C. Assume that Do is 1.9 x 105 m²/s and Quis 108 kJ/mol, 3.89 -land Madin h
For a steel alloy it has been determined that a carburizing heat treatment of 11.4h duration will raise the carbon concentration to 0.410 wt% at a point 2.10 mm from the surface. Estimate the time necessary to achieve the same concentration at a 4.60 mm position for an identical steel and at the same carburizing temperature. i
To increase the hardness of a steel gear, it was carburized at 850oC by introducing 1.3%C at its steel surface. What will be the final carbon content 1.4 mm beneath the surface if this treatment was lasted for 26 hours. The initial carbon content of steel is 0.1%C. (gas constant is 8.31 j/mol.K)
Given that a component is made of 0.1 wt.%C steel is carburized by introducing 1.0 wt.% carbon at its surface at 980ºC. Calculate the carbon content at 0.5 mm below the surface of this component after 1 hour.Do= 0.2 cm^2/s and Qd=40,000 cal/mol.
In precipitation hardening, after being quenched into solution, overcooling is done and then either artificial aging is done at 180-250°C or natural aging is done at room temperature, both of which occur through diffusion, where temperature and time parameters are dominant. While 180°C and 250°C provide sufficient temperature for diffusion, is it not interesting that diffusion occurs at room temperature? This is because of the thermal energy of atoms causing them to move, which may facilitate diffusion at room temperature.
Determine the carburizing time necessary to achieve a carbon concentration of 0.50 wt% at a position 1.2 mm into an iron-carbon alloy that initially contains 0.18 wt% C. The surface concentration is to be maintained at 1.1 wt% C, and the treatment is to be conducted at 1200°C. Assume that Do 6.5 x 10-5 m2/s and Qd = 168 kJ/mol. The following table may be useful. %3D Table 5.1 Tabulation of Error Function Values erf(z) erf(z) erf(z) 0.55 0.5633 1.3 0.9340 0.0282 0.0564 0.025 0.60 0.6039 1.4 0.9523 0.05 0.10 0.65 0.70 0.75 0.6420 1.5 0.9661 0.1125 0.6778 1.6 0.9763 0.15 0.1680 0.7112 1.7 0.9838 0.20 0.2227 0.80 0.7421 1.8 0.9891 0.85 0.90 0.25 0.2763 0.7707 1.9 0.9928 0.9953 0.9981 0.30 0.3286 0.7970 2.0 0.35 0.3794 0.95 0.8209 2.2 0.8427 0.8802 0.40 0.4284 1.0 2.4 0.9993 0.45 0.4755 1.1 2.6 0.9998 0.50 0.5205 1.2 0.9103 2.8 0.9999
Determine the carburizing time necessary to achieve a carbon concentration of 0.50 wt% at a position 3.1 mm into an iron-carbon alloy that initially contains 0.12 wt% C. The surface concentration is to be maintained at 1.2 wt% C, and the treatment is to be conducted at 1080°C. Assume that Do = 5.8 x 10-5 m²/s and Qd = 156 kJ/mol. The table Tabulation Error Function Values may be useful.
•You are case-hardening a tool made of BCC (α) iron in the presence of a carbonaceous material. A heat treatment at 600 oC for 100 minutes results in a carbon concentration of 0.75 wt% at a position 0.5mm below the surface. How long would it take to obtain the same concentration at the same position if the heat treatment were conducted at 900 oC? x12/D1t1= x22/D2t2 Arrhenius equation: D=D0e^(〖-Qd〗∕RT) Qd = Activation energy of diffusion D0 = Pre-exponential diffusion factor R = gas constant = 8.314 J/(mol*K) Use the Arrhenius equation to calculate D1 and D2. Calculate the time to satisfy the problem statement.

SEE MORE QUESTIONS

Recommended textbooks for you

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

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

SEE MORE TEXTBOOKS