Engineering Materials Technology II
Assignment 01 Answers
Year 2025
0027 63 985 5033
,
,
,
, QUESTION 1
In modern vehicles, engine covers are an important accessory for both functionality and
aesthetics. It covers the engine compartments from debris, noise reduction, and beautification
of the engine bay. Selection of materials and manufacturing processes is crucial to the startup
in a garage wishing to produce an effective quality engine cover for performance, cost, and
durability.
(RTM)Process: In this closed molding process, the fibers are first placed in the mold (e.g.,
carbon, fiberglass). The particular liquid resin (epoxy, polyester) is then injected into the mold
under pressure.
Reinforced Reaction Injection Molding (RRIM)Process: Very fast curing and the process
is where polyurethane resin is mixed together with short fibers and fillers and injected into the
mold.
Construction of engine covers involves the tasks under: material selection, molding
process and mold manufacturing.
For engine covers the material has to be:
High strength/weight ratio-for resisting vibration and shock.
Heat resistance-in engine environments between 120 0C and 2000C
Chemical resistance-against oils, fuels and cleaning agents.
Recommended materials are as follows:
Reinforced composites: RTM/RRIM
Epoxy or polyester resin (RTM): high strength; excellent adhesion to fibers.
Polyurethane (RRIM): very fast cycle times; and increased impact resistance.
Reinforcements include the following:
Carbon fiber: an expensive source (high strength, low weight).
Fiberglass: a cheaper one (provides good mechanical properties).
Aramid (Kevlar): provides impact resistance.
Assignment 01 Answers
Year 2025
0027 63 985 5033
,
,
,
, QUESTION 1
In modern vehicles, engine covers are an important accessory for both functionality and
aesthetics. It covers the engine compartments from debris, noise reduction, and beautification
of the engine bay. Selection of materials and manufacturing processes is crucial to the startup
in a garage wishing to produce an effective quality engine cover for performance, cost, and
durability.
(RTM)Process: In this closed molding process, the fibers are first placed in the mold (e.g.,
carbon, fiberglass). The particular liquid resin (epoxy, polyester) is then injected into the mold
under pressure.
Reinforced Reaction Injection Molding (RRIM)Process: Very fast curing and the process
is where polyurethane resin is mixed together with short fibers and fillers and injected into the
mold.
Construction of engine covers involves the tasks under: material selection, molding
process and mold manufacturing.
For engine covers the material has to be:
High strength/weight ratio-for resisting vibration and shock.
Heat resistance-in engine environments between 120 0C and 2000C
Chemical resistance-against oils, fuels and cleaning agents.
Recommended materials are as follows:
Reinforced composites: RTM/RRIM
Epoxy or polyester resin (RTM): high strength; excellent adhesion to fibers.
Polyurethane (RRIM): very fast cycle times; and increased impact resistance.
Reinforcements include the following:
Carbon fiber: an expensive source (high strength, low weight).
Fiberglass: a cheaper one (provides good mechanical properties).
Aramid (Kevlar): provides impact resistance.
