F2023_M202_A6

Hey may you please help me with these Material science questions. 1) Give a brief explanation why the hardness of hardend steel will decrease with tempering 2)  Give a brief explanation why the solubility of C is higher in g-iron than in a-iron. 3)  Why must the samples be quenched rapidly to obtain high hardness? 4) Screenshot!

1.50% Pearlite, 50% Tempered Martensite 2.50% Bainite, 45% Martensite, 5% Austenite

1. Why does the tensile strength of steel, which contains only austenite at room temperature, differ fromsteel that shows only pearlite in its microstructure? Give two important reasons for the difference.  2. What general prerequ_isites exist for the formation of martensite in steel? 3. What is an isothermal transformation of a material in the solid state condition? 4. Draw a typical isothermal transformation diagram for plain .carbon eutectoid steel and indicate thevarious decomposition products expected by simple diagrammatic drawing.

The TTT diagram for a 1077 eutectoid steel is given. Explain the heat treatment process to form 50% Fine Pearlite + 50% Coarse Bainite. 800 A 1400 Eutectoid temperature 700 A 1200 600 1000 500 B 800 400 A 300 600 M(start) 200 M + A 50% 400 M(50%) М190%) 100 200 10-1 1 10 102 103 104 105 Time (s) Temperature (°C) Temperature (°F)

Use the TTT diagram for O1 Tool steel provided above to estimate the amounts ofpearlite and martensite formed in the quenched heat-treated samples.

a: Quench to from 800oC to 650oC and hold for 10 seconds:b: Next, quench the alloy to approximately 350oC and hold for 102 secondsc: Next, quench the alloy to approximately 175oC and hold for 10 secondsd: Finally, quench the alloy to room temperature

2) There is an aluminum-copper alloy. The phase diagram is given below. What heat treatment do you apply? Using this graph, how is it possible to increase the strength and hardness of this alloy? Consider this question within the scope of heat treatments. Composition (at % Cu) 10 20 30 700 1200 600 L a+ L 0 +L 1000 a 500 (CuAl,) a + 0 800 400 600 300 10 20 30 40 50 (AI) Composition (wt% Cu) Temperature (°C) Temperature (°F)

Draw Iron - Iron Carbide Phase diagram and show the following: 1- Temperature, phases and carbon weight for Eutectic. 2- Temperature, phases and carbon weight for Eutectoid Thecementite, 3- austenite, ferrite, delta phases with their 4- Types of ferrous alloys on different carbon rates. 5- Draw the phase at T= 700 CD and 0.7 wt% C what is its name ? temperatures and carbon weight.

Please do not copy/repost previous diagrams from chemistry Q&A.  Either place path drawing on or use same EXACT axis labeling as the diagram.

For a Fe-C alloy with a eutectoid composition, an austenite was rapidly cooled down to 450°C, held for 10 sec, and quenched to room temperature. What is the final microstructure based on its TTT curve? Amount Temperature of Transformation, C 700 600 500 400 300 200 Ae₂! Ae₁ Austenite unstable Ms. 10 10² 103 104 105 seconds Austenite stable 50%- 100 MF TELEP P 100% completed F+B Coarse Pearlite - Fine Pearlite -Upper Bainite (Feathery) Lower Bainite → Martensite + Bainite Martensite 1 1sec 1 min 1hr Transformation Time (Log. Scale) O a. 50% bainite and 50% martensite O b. 50% austenite and 50% bainite O c. 100% bainite O d. 100% martensite Finer Lamellac Bainitic Pearlitic Austenite Fine more Acicular Rapid Etching Martensitic cicular, Slow Etching V.P.H. 210 320 450 700 750

Material science

Can anyone help with this question

Based on the IT diagram for an iron-carbon alloy of eutectoid composition, specify the final microstructure (in terms of microconstituents present and percentages of each) of a specimen subjected to the following time-temperature treatments Cool rapidly to 650oC, hold for 104s then quench Reheat the specimen in (a) to 700oC for 20h  Cool rapidly to 400oC hold for 2s then quench to room temp Cool rapidly to 400oC hold for 20s then quench to room temp Cool rapidly to 575oC hold for 20s, cool rapidly to 350oC hold for 100s then quench to room temp.

Question 7: The illustration shows the iron-carbon phase diagram. 1600 1400 1200 1000 800 600 400 1538°C 0 (Fe) 1493°C 1394°C 912°C 7. Austenite 0.76 0.022 a, Ferrite Y+L 2.14 Composition (at%C) 15 10 1147 C a+FezC Y+FeyC 4 3 Composition (wt% C) 727 C Cementite (FeyC). 2500 2000 1500 1000 6.70 Temperature (°F) e) Describe the changes in phase compositions of a carbon steel with a carbon content of 1 % (weight-%) from 1500°C down to 727°C with the help of the attached phase diagram and appropriate equations/reactions.

Answer the following questions using the phase diagram of iron and iron carbide below:For a 99.70 wt% Fe–0.30 wt% C alloy at a temperature of 600oC, determine the following:a. The fractions of total ferrite and cementite phases b. The fractions of the pro eutectoid ferrite and pearlite

Please explain ths graph from Materials Science and EngineeringAn Introduction

13- Copper-rich copper-beryllium alloys are precipitation hardenable. After consulting the portion of the phase diagram shown in the figure below, do the following: (a) Specify the range of compositions over which these alloys may be precipitation hardened. Temperature (°C) (b) Briefly describe the heat-treatment procedures steps (in terms of temperatures) that would be used to precipitation harden an alloy having a composition of 1 wt% Be. 1000 800 600 400 0 (Cu) 0 1 Composition (at% Be) 10 15 a + L 2 α + 1/2 Liquid Composition (wt% Be) 866°C -620°C 3 20 x + 1₁

800 A Eutectoid temperature H 1400 700 A H 1200 600 1000 500 B 800 400 A 300 600 M(start) 200 M + A 50% 400 M(50%) M(90%) 100 200 10-1 1 10 102 103 104 105 Time (s) Using the isothermal transformation diagram for an iron-carbon alloy of eutectoid composition, specify the final microstructure and approximate amount of each. Assume a small specimen has been held long enough to have achieved a complete and homogeneous austenitic structure prior to treatment. Sample (1): Quickly cool specimen from 800°C to 575°C, hold for 10 s, then quench to room temperature. Sample (2): Quickly cool specimen from 800°C to 500°C, hold for 100 s, then quench to room temperature. O after treatment, sample 1 is 50% pearlite, 50% austenite O after treatment, sample 2 is bauxite O after treatment, sample 1 is 25% pearlite O after treatment, sample 2 is bainite O after treatment, sample 2 is austenite O None of the answers is correct. O after treatment, sample 2 is coarse pearlite O after treatment, sample 1 is…

7 what would be the resulting microstructure from heat treatment?

I need answer within 20 minutes please please with my best wishes

a: Quench to from 800oC to 350oC and hold for 102 seconds:b: Quench the alloy to room temperaturec: Reheat the alloy to 700oC and hold for 105 seconds

Copper-rich copper-beryllium alloys are precipitation hardenable. After consulting the portion of the phase diagram shown in Figure below, do the following: Composition (at% Be) 10 15 20 Liquid 1000 866°C 800 -620°C 600 a+ 400 2 3. (Cu) Composition (wt% Bo) (1) Indicate the range of compositions over which these alloys be precipitation hardened. (ii) Describe the heat-treatment procedures (in terms of temperatures) that would be used to precipitation harden an alloy having a composition of your choosing but lying within the range given for part (i). Temperature ("O

Using the isothermal transformation diagram for an iron-carbon alloy of eutectoid composition, sketch (mark the microconstituents, eg. a-Fe, Fe,C) and specify the name of the final microstructure (e.g. austenite, pearlite, bainite etc.) of a small specimen that has been subjected to the following time-temperature treatment. In each case assume that the specimen begins at 760 Cand that is has been held at this temperature long enough to have achieved a complete and homogeneous austenite structure. 800 -Eutectoid temperature 1400 700 1200 600 1000 500 800 400 300 600 Mistart) 200 50% 400 ME50%) M90%) 100 200 10 10 10 10 10 10 Time ( eoha ileySons, lnc. Al righta reserved (a) Cool rapidly to 350 S, hold for 10' s, then quench to room temperature (b) Cool rapidly to 665 S, hold for 10's, then quench to room temperature (c) Cool rapidly to 150gin 5 seconds, then cool to room temperature (d) Cool rapidly to 300gin 1 second, then cool to room temperature in 10s (3J anjedueI Temperature F)

Part C. Which type of phase transformation is important in heat treatment of steels? (circle one)Peritectic Eutectic Eutectoid Incongruent meltingAt what temperature and overall composition wt% C, does it occur?Write the reaction equation for this transformation, and briefly describe the nature of each of the three important phases that are involved.

For each question, provide an explanation, identifying the correct choice ( it is marked in red)  and explaining why it's the right answer, as well as why the other options are incorrect.

Using the TTT diagram for eutectoid steel, draw the specified cooling path on the diagram. Indicate what phases you expect in the final product with percentage of each phase. Assume the material has been fully austenitized before cooling. a. Water cool to room temperature b. Hot quench in molten salt to 690°C and then cooled isothermally for 2 hours: c. Hot quench to 610°C hold 3 minutes and water quench

1. Draw a diagram of the gray and nodular gray cast iron's substructure. 2. Comment on the gray wrought iron's mechanical characteristics. 3. Describe a scenario in which cast iron would be used in manufacturing such in engineering

Below is a continuous cooling transformation curve for steel (upper) and for a silicate melt (lower). Describe the similarities and differences as follows. a. What is the critical cooling rate in each case? b. What phase(s) form in each case when the critical cooling rate is exceeded? c. What phase(s) form in each case if the cooling rate is very slow? 800 1400 Ae lemperature Austenite *peorlite begins 10FI 700 1200 Austenitepearlite complete 1600 1000 5009 800 Tronsformation stops 400 600 300 400 Austenite -mortenstic structure 200 -Isathermal dogram Continuous transformaton diogrom Constant rate coding curves - 100 200 Findl structure Mortensite Morlensite i peorlile Peorite (softer, coorser- 0.1 10? 10 Tronsformation time, seconds Continuous Cooling-Transformation (C-T)Diagram (Derived from the isothermal-transformation diagram for a plain-carbon eutectoid steel) 1200 Glass Crystallization begins 1100 1000 Critical cooling rate Glass-ceramic 900 Crystallization ends 800 700 102 10…

3 Materials Science. From picture below.Describe in detail the phase transformations (showing cooling curves, corresponding optical backgrounds, etc.) that takes place during solidification of the following alloys:(a) 99% Cu - 1% Al(b) 96% Cu - 4% Al(c) 80% Cu - 20% Al

1. What is wrought iron in gray? 2.  Why does gray cast iron lack tensile strength? 3. What can you do to give gray wrought iron a little toughness?

3. What effects do the alloying additions have on the microstructure and mechanical properties of air-cooled (normalized) steel specimens? 1 4. What effects do the alloying additions have on the microstructure and mechanical properties of furnace-cooled (annealed) steel specimens?