Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Cylinder Series Test
A series of round bars of various diameters are austenitized and quenched into oil or water. The bars are long sufficient hence the cooling of section at the middle of the length is not affected via the ends. After hardening every bar is cut in half and hardness measured on different points along a diameter. The graph in between distance and hardness from the centre is then prepared as in following figure. From such graph the diameter at that 50% of the structure is martensite is calculated. While such graph the diameter is plotted against bar diameter, this becomes possible to find out the bar diameter whether 50% martensite would form at the centre. This is termed as critical diameter for such quenching medium. Because the rate of cooling is less for oil quench after that for water quench, the critical diameter, of any type of steel will be less for oil quenching than for two water quenching. Quench severity is an index in which quantitatively explains the quenching situation. Such index indicated by H is explains as given ratio.
H = Heat transfer coefficient between steel and fluid/Thermal conductivity of steel
Figure: Variation of Hardness along with Depth in Water-quenched Cylindrical Bars of (a) Plain Carbon Steel, (b) 1% Cr-V Alloy Steel
Obviously, when H → ¥, it shows the severest condition of quench, sense that surface of steel instantly reaches the quenching medium temperature. The critical diameter for that, an unrealizable and ideal situation is termed as ideal critical diameter. For infinite H-value ideal critical diameter and the critical diameter will be similar. For other H values the critical diameter will be slighter. Given figure illustrates the relationship in between ideal diameters and critical diameters for various H-values. Table no.10 illustrates relative values of H such can be acquired in different quench media beneath various condition along with value of one for still water as base.
Figure: Relation between Critical Diameter, Ideal Critical Diameter and Severity of Quench
Table no: Relative Quench Severities
Agitation of Quenching Medium
Movement of
Pieces
Severity of Quench
Air
Oil
Water
Brine
None
0.02
0.3
1.0
2.2
Moderate
-
0.4 - 0.6
1.5 - 3.0
Violent
0.6 - 0.8
3.0 - 6.0
7.5
Violentor spray
1.0 - 1.7
6.0 - 12.0
Seasonal-Component Analysis: A food processor uses a moving average to forecast next month's demand. Actual demand data for the past few months is available as depicted in the
It shows the test rig for the assignment of an indeterminate structure at the Materials Lab. The indeterminate structure consists of three pin-jointed members made of the same stee
Applications. The welding process finds widespread applications in almost all branches of industry and construction. fabrication and creation of steel structures
FRICTION WELDING In this, friction is employed to generate heat b/w two sliding or rotating metal surfaces. This process is usually carried out by placing the pieces to be welded
Relation between stress and strain: The relation between stress and strain is generally shown by plotting a stress-strain (σ -e) diagram. Stress can be plotted on ordinate (ve
Once vendor drawings are received and piping isometric drawings are prepared, the Mechanical engineer will provide a final stress package to the stress engineer per The stress a
AUTOMOBILES INDUSTRY GROWTH: The Indian automobile industry has a significant labour cost advantage. India's automotive sector has the world's second largest pool of skilled labou
Q. What do you mean by Velocity - Area Method? Out of the above four categories, velocity area method is most widely used and provides more accurate results. Requirements of a
Determine reactions force: Thr e e sphere A , B and C weighing 400N, and 200N and having radii 400mm, 600mm and 400mm respectively are placed in trench as shown in t
(a) What is transmission system? Represent the main components of transmission system with the help of diagram. (b) What do you mean by terms torque, power and RPM? (c) What
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd