The temperature required for full annealing in hypereutectoid steel is

A 30° C to 50° C above upper critical temperature
B 30° C to 50° C below upper critical temperature
C 30° C to 50° C above lower critical temperature
D 30° C to 50° C below lower critical temperature

Correct Answer: 30° C to 50° C above lower critical temperature

Full annealing is the process of slowly raising the temperature about 50 ºC (122 ºF) above the Austenitic temperature line A3 or line ACM in the case of Hypoeutectoid steels (steels with 0.77% Carbon).
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Related Questions

In process annealing, the hypo eutectoid steel is
A Heated from 30°C to 50°C above the upper critical temperature and then cooled in still air
B Heated from 30°C to 50°C above the upper critical temperature and then cooled suddenly in a suitable cooling medium
C Heated from 30°C to 50°C above the upper critical temperature and then cooled slowly in the furnace
D Heated below or closes to the lower critical temperature and then cooled slowly
Protective gas used in the annealing furnace for steel coil comprises of
A 95% N2 + 5% H2
B 5% H2 + 95% N2
C 100% CO
D 100% H2
A steel mill produces 180 tons of steel per month Raw materials cost for each ton of production is Tk. 1200. Other expenses of that mill are Tk. 90,000 in each month what should be the selling price of each ton of steel in order to make 10% profit?
A 1870
B 1845
C 1842
D 18145
10 cm লম্বা ও 0.5 cm ব্যাসার্ধ বিশিষ্ট একটি তামা ও একটি লোহার তারকে জোড়া লাগিয়ে দৈর্ঘ্য 20 cm করা হল। জোড়া লাগানো তারটিকে বল প্রয়োগ করে লম্বা করা হল। লোহার ইয়ংয়ের গুণাঙ্ক তামার ইয়ংয়ের গুণাঙ্কের দুইগুণ হলে লোহার দৈর্ঘ্য বৃদ্ধি ও তামার দৈর্ঘ্য বৃদ্ধির অনুপাত কত? ( A steel and a brass wire, both having 10 cm length and 0.5 cm radius, are joined together making the total length of the combined wire 20 cm. The combined wire is stretched by applying a force. If the Young's modulus of steel is twice as much as that of brass, what will be the ratio of the extension of steel to the extension of brass?)
A 1 :8
B 1 : 6
C 1 : 4
D 1 : 2
The cutting speed for drilling aluminium, brass and bronze with carbon steel drills is _________ cutting speed for drilling mild steel with high speed steel drills.
A Equal to
B Less than
C More than
D None of these
10 cm লম্বা ও 0.5 cm ব্যাসার্ধ বিশিষ্ট একটি তামা ও একটি লোহার তারকে জোড়া লাগিয়ে দৈর্ঘ্য 20 cm করা হল। জোড়া লাগানো তারটিকে বল প্রয়োগ করে লম্বা করা হল। লোহার ইয়ংকের গুণাস্ক তামার ইয়ংকের গুণাস্কের দুইগুন হলে লোহার দৈর্ঘ্য বৃধি ও তামার দৈর্ঘ্য বৃদ্ধির অনুপাত কত? (A steel and a brass wire, both having 10 cm length and 0.5 cm radius, are joined together making the total length of the combined wire 20 cm. The combined wire is stretched by applying a force. If the Young‘s modulus of steel is twice as much as that of brass, what will be the ratio of the extension of steel to the extension of brass?)
A 1:8
B 1:6
C 1:4
D 1:2
With increase in annealing temperature, the following defect density decreases.
A Vacancy
B Dislocation
C Grain boundary
D All of them
The 'transition temperature' for ductile to brittle behaviour of steel increases with increase in the __________ content in steel.
A Carbon
B Manganese
C Both A & B
D Neither A nor B
__________ iron is produced by the annealing of white cast iron.
A Malleable
B Nodular
C Ductile
D Grey
Which of the following statements are true for annealing of steels?
A Steels are heated to 500°C to 700°C
B Cooling is done slowly and steadily
C Internal stresses are relieved
D All of these

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