A-For a carburization process taking place at 779.9 K, use the standard BCC iron activation energy and diffusion constant to calculate the time needed to reach a concentration of 0.4 at a depth of 64 micrometers, if the initial carbon concentration of the steel is 0.1 wt% and the imposed surface concentration is equivalent to 1.2 wt%.
b-
For a carburization process taking place over 412 seconds, use the standard BCC iron activation energy and diffusion constant to calculate the temperature in K needed to reach a concentration of 0.6 at a depth of 94 micrometers, if the initial carbon concentration of the steel is 0.1 wt% and the imposed surface concentration is equivalent to 1.7 wt%.
A-For a carburization process taking place at 779.9 K, use the standard BCC iron activation energ...
For a carburization process taking place over 193 seconds, use the standard BCC iron activation energy and diffusion constant to calculate the temperature in K needed to reach a concentration of 0.5 at a depth of 48 micrometers, if the initial carbon concentration of the steel is 0.1 wt% and the imposed surface concentration is equivalent to 1.5 wt%.
1) You find that carbon takes 259 s to diffuse to a concentration of 0.5 wt% at a depth of 0.1 mm in BCC iron if the intitial concentration is 0.2 wt% and the surface is maintained at 1 wt% at 863 K. At temperature 888 what diffusion time will be needed? 2) You find that carbon takes 553 s to diffuse to a concentration of 0.5 wt% at a depth of 0.1 mm in BCC iron if the intitial...
3. For the carburization process in problem #2 above the surface carbon concentration is at 1.0 wt% C. The initial carbon concentration of the steel is 0.2 wt%. Calculate how long it will take at 10000C to reacha carbon concentration of 0.6 wt% at a distance of 1 mm from the surface. Assume this is a semi-infinite solid. region. The density of y-iron (FCC) at 1000°C is 7.63 g/cm3, Do = 20x106 m2/s; Q = 142,000 J/mol
Please answer all the three questions.. Please please 7. (8 points) Carburization is an industrial process to harden steel components through diffusion. It is done at elevated temperature because a. Steels have high yield strength b. Catoms can penetrate into the component's surface through vacancy diffusion c. Catoms can penetrate into the component's surface through interstitial diffusion d. Diffusivity is high at elevated temperature 8. (15 Points) The bonding energy Ex between two atoms is a function of interatomic distance...
6.5 18. (8 pts) The Diffusivity of nitrogen in y-iron is 4 times higher at 1200°C than at 950 C. (a) Find the activation energy for nitrogen diffusion in iron. R 1.987 cal/mol-K Do exp (1.987- wal vevisit lo ala exo 29 26, 451 l 2430. 10 alalS 29 24.851 2430 29 2a 24 30. 19. (10 pts) To improve the wear resistance of a steel gear, a carburization process is employed to harden the surface of the machine element...
Please show work for problems 1-4 1. Calculate the activation energy for vacancy formation in aluminum, given that the equilibrium number of vacancies at 500°C (773 K) is 7.57 x10m3. The atomic weight and density (at 500°c) for aluminum are 26.98 g/mol and 2.62 g/cm, respectively 2. What point defects are possible for Al,0, as an impurity in Mgo? How many Al ions must be added to form each of these defects? 3. A sheet of steel 4.5 mm thick...
UTVER VIS Concentration of Nitrogen (wt%): = 0.21 Position in mm= 7.2 Diffusion Coefficient for Nitrogen in Iron at 700°C -8.90E-10 Nitrogen in Iron Heat Treatment Time (hours): = 8 Carburizing Time (hrs): = 7 Steel Alloy Case Depth (mm): 4.8 Steel Alloy New Case Depth (mm) - 9.9 Activation Energy kJ/mol: = 103 Temperature for Problem 3 (Celsius) -809 . Data for Problem 4 Temperature in C: -595 Diffusivity (m2/s) = 5.62E-14 Temperature in C: -702 Diffusivity (m /s)...
In the carburizing process the steel piece was exposed, at an elevated temperature (900 °C), to an atmosphere rich in a hydrocarbon gas, such as methane CH Surface concentration of carbon is to be maintained at 1.18 wt%. Determine the time (in hours) necessary to achieve a carbon content of 0 68 wt% at a position 0.8 mm below the surface. Initial carbon concentration is 0 18 wt% Take the diffusion coefficient for carbon in iron at 900°C = 1.0...
please answer highlighted part only and detailedely thank you compare and co describe one industrial application in which steady state diffusion plays an important role, use sketches as needed; (c) An FCC iron-carbon alloy initially containing 0.22 wt% carbon is carburized at an elevated temperature and in an atmosphere wherein the surface carbon concentration is maintained at 1.1 wt% carbon. If after 50.0 hours the concentration of carbon is 0.47 wt% at a position 2.2 mm below the surface, determine...
Questions and Problems 167 Fick's Second Law-Nonsteady-State Diffusion 5.D3 The wear resistance of a steel shaft is to be im proved by hardening its surface by increasing the nitrogen content within an outer surface layer as a result of nitrogen diffusion into the steel; the nitro- gen is to be supplied from an external nitrogen-rich gas at an elevated and constant temperature. The initial nitrogen content of the steel is 0.0025 wt%, whereas the surface concentration is to be main-...