MMET 207 Final Exam Questions with Complete Solutions
6 views 0 purchase
Course
PNR 207
Institution
PNR 207
Bainite is a mixture of needles of carbide and austenite. - Answer-False
The hardness of martensite goes down gradually during tempering at room temperature subsequent to quenching. - Answer-False
Higher the tempering temperature, smaller is the tempering time needed. - Answer-True
Banite ...
MMET 207 Final Exam Questions with
Complete Solutions
Bainite is a mixture of needles of carbide and austenite. - Answer-False
The hardness of martensite goes down gradually during tempering at room temperature
subsequent to quenching. - Answer-False
Higher the tempering temperature, smaller is the tempering time needed. - Answer-True
Banite is tougher and harder than pearlite. - Answer-True
Tempering increases the hardness of quenched steels. - Answer-False
Steel refining means making steel from pig iron, scrap, or ore. - Answer-True
The source of heat in the electric arc furnace is an arc that is established between the
melt and graphite electrodes. - Answer-True
Electric arc furnaces can not be shut down between uses. - Answer-False
Segregation can be minimized by adding elements to the steel, such as aluminum and
chromium. - Answer-False
Hot-finished steels have lower mechanical properties than cold-finished steels. -
Answer-True
One of the two primary steel making processes is - Answer-EAF - electric arc furnace
In hot finishing, ingots are rolled to smaller shapes such as - Answer-Billets
Ferrite consists of FCC iron structure with carbon in solid solution - Answer-False
Longer tempering times are needed at higher temperatures then at lower temperatures.
- Answer-False
Both Ms and Mf temperatures decrease with increasing carbon content in steels. -
Answer-True
The grain size in austempered steels is coarse because of rapid grain growth. - Answer-
False
Bainite is harder than pearlite. - Answer-True
, More martensite is formed during subsequent cooling after quenching to room
temperature if room temperature is between Ms and Mf temperature. - Answer-True
Martensite is hard and tough. - Answer-False
In all heat treatment of steel the transformation of austenite is important. - Answer-True
Quench cracks are due to retained austenite in steels changing over to bainite. -
Answer-False
To form martensite, the critical cooling rate should be exceeded when the steel is
cooled. - Answer-True
Tempering is done in the tempering range 700-1200 degrees. - Answer-False
Hardenable steels are excellent for welding purposes because they have high
resistance to cracking. - Answer-False
Adding Nickel as an alloying element will increase toughness. - Answer-True
Adding Silicon as an alloying element will increase - Answer-Hardenability
Martensitic stainless steels are hardenable by heat treatment. - Answer-True
Ferritic stainless steels are hardenable by cold working. - Answer-False
Austenitic Stainless Steels have excellent weldability by almost all welding processes. -
Answer-True
Stainless steels are prone to crevice corrosion. - Answer-False
Stainless steels do not perform best in oxidizing environments. - Answer-False
The prefix, E, signifies a steel that is - Answer-made in the electric arc furnace
Which of the following is a physical property?
a. color
b. hardness
c. microstructure
d.valence
e. electronegativity
f. composition - Answer-Color
hardness = mechanical property
microstructure = chemical property
valence = chemistry term
electronegativity = chemical property
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller lectknancy. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $15.49. You're not tied to anything after your purchase.
