WorksheetsEME 452 Tribology
Total questions: 25
Worksheet time: 15mins
Composition of lubricants normally consists of.....
Base oil and additives
Based oil and metal
Based oil and fillers
Petroleum and inorganic element
The ideal of lubrication regimens in Stribecks curve indicates........................... lubrication.
Boundary lubrication
Mixed lubrication
Elastrohydrodynamic lubrication
Hydrodynamic lubrication
All of above
In designing the component in Tribology of Total Hip Replacement (THR), one must consider.....(the answer is more than one, choose wisely)
Force
Counter bodies contact
Sliding distance
Materials used
The factor influencing fluid film lubrication formation consists of......(answer could be more than 1, hence choose wisely)
Material properties
Viscocity of fluid
Diameter of asperities tool
Surface Roughness
Which of the following answers is the most scientific answer for the question:
What is friction?
The random force between two solids, liquids, or gases.
The contact force between two solids, liquids, or gases that slide past one another.
The thing that creates static electricity
A force that is random
Force and roughness between surfaces
hills and valleys and how smooth or rough the surface is
Amount of force and amount of surface the comes in contact
The force and the weight exerted on the surfaces
What is the study of Wear, Friction and Lubrication called? (check your spelling)
(a)
Wear mode listed below is correct combination EXCEPT
(i) adhesive
(ii) abrasive
(iii) corrosive
(iv) embedded
(v) fatique
(i), (ii), (iii) & (iv)
(i) & (v)
(i), (ii), (iii) & (v)
(i), (ii) & (v)
(i), (iii) & (v)
Adhesion component of dry friction is negligible at interface of
high temperature surfaces
adhesion between two surfaces
lubricated tribo-pair
extra smooth surfaces
To avoid stick slip phenomenon due to friction instability, which condition is the right approach?
increase operation speed
decrease operation speed
no effect on speed
increase the difference between static and kinetic COF
As per Archard's wear equation, Q=HkWL ; wear volume in adhesive wear is independent of........
sliding distance
load
hardness of the soft materials
rolling distance
In hydrodynamic lubrication, the major source of friction is..........
abrasion of asperities on tribo-surfaces
shearing of lubricant film
abrasion of tribo-surfaces due to free particles
all of above
Mode of wear mechanisms are listed below EXCEPT:
adhesion
abrasion
tribo-corrosion
impingement
fatigue
In which lubrication regime does the lubricant completely separate the two surfaces?
Boundary lubrication
Elastrohydrodynamic lubrication
Mixed lubrication
Hydrodynamic lubrication
What is the primary cause of wear in abrasive wear mode?
Thermal expansion
Hard particles scratching the surface
Adhesion between surfaces
Corrosion of materials
Which of the following is a characteristic of static friction?
It acts when surfaces are in motion
It can vary with the weight of the objects
It is always less than kinetic friction
It does not depend on the surface texture
In which lubrication regime does the lubricant film start to break down?
Boundary lubrication
Elastrohydrodynamic lubrication
Hydrodynamic lubrication
Mixed lubrication
What is the primary function of lubricants in reducing friction?
To increase the temperature of the surfaces
To change the color of the surfaces
To create a barrier between surfaces
To enhance the adhesion between surfaces
