Given the following TTT curve for a modified eutectoid steel. Tell what phases exist in the...

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Given the following TTT curve for a modified eutectoid steel. Tell what phases exist in the steel at the end of each of these successive steps. Also sketch the final microstructure. (a) Heat to 800 C for one hour. (b) Quench to 600 C and hold for 10 sec. (c) Quench to room temperature. (d) Reheat to 300 C for one hour. 800 Ystable hat el hese 600 d+ FeC Temp. 400- Yrd+ Fes Yunstable 200 Ms 8+M 0 Mf M -200+ 0.1 1.0 10 100 1000 Time (s) Q6(a) State one challenge in recycling polymeric material. (1 mark) (b) State the principle and the objective in developing biodegradable polymer. (5 marks) (c) Discuss two applications of biodegradable polymers. (4 marks) (d) Other than biodegradable polymer, discuss other attempts been done to reduce to polymer waste. (6 marks) Given the following TTT curve for a modified eutectoid steel. Tell what phases exist in the steel at the end of each of these successive steps. Also sketch the final microstructure. (a) Heat to 800 C for one hour. (b) Quench to 600 C and hold for 10 sec. (c) Quench to room temperature. (d) Reheat to 300 C for one hour. 800 Ystable hat el hese 600 d+ FeC Temp. 400- Yrd+ Fes Yunstable 200 Ms 8+M 0 Mf M -200+ 0.1 1.0 10 100 1000 Time (s) Q6(a) State one challenge in recycling polymeric material. (1 mark) (b) State the principle and the objective in developing biodegradable polymer. (5 marks) (c) Discuss two applications of biodegradable polymers. (4 marks) (d) Other than biodegradable polymer, discuss other attempts been done to reduce to polymer waste. (6 marks)