Material Mania

1. Piston Of Car Engines:

The name 'piston' itself reminds us of the strenuous thermodynamics problems of air either leaking out of the cylinder or being forced into it with the movement of piston. But have you ever thought what pistons are made up of?

1.1. Methods:

By casting molten aluminium alloy (used both in gasoline and diesel engines) or by forging

By Gravity die casting

By Squeeze Casting

1.2. Materials:

Mono-metal aluminium pistons and aluminium piston with cast-in elements are used in cast iron engine blocks.

Aluminium oxide fibre-reinforce bottoms used in direct injection diesel engines.

The standard piston alloy is a eutectic Al-12%Si alloy containing approximately, 1% each of Cu, Ni and Mg.

Special eutectic alloys have been developed for improved strength at high temperatures.

1.3. Advantages of Aluminium:

Light weight

High structural strength

2. Use of polymers in vehicles:

Light vehicles represent an important plastics market for and Polymer composites, one that has grown significantly during the last five decades. The average North American light vehicle now contains 851 pounds of plastics and polymer composites, 8.8% of the total weight Although this is off from the prior peak in 2009, it is up from 343 pounds in 2010, 279 pounds in 2000 and 156 pounds in 1990. In 1960, less than 20 pounds were used. The typical light vehicle may contain over than 1,000 plastic parts.

Composites are any combination of polymer matrix and fibrous reinforcement. Glass, carbon, aramid, and other fibers provide strength and stiffness while the polymer matrix (or resin) of polyester, polyurethane, epoxy, polypropylene, nylon, or other resin protects and

transfers loads between fibers. This creates a material with attributes superior to polymer or fiber alone. In recent years, carbon fiber reinforced composites have made inroads into light vehicle applications. Plastics and polymer composites have been essential to a wide range of

safety and performance breakthroughs in today's cars, minivans, pickups and SUVs. Today's plastics typically make up 50% of the volume of a new light vehicle but less than 10% of its weight, which helps make cars lighter and more fuel coefficient, resulting in lower

greenhouse gas emissions. Tough, modern plastics and polymer composites also help improve passenger Safety and automotive designers rely on the versatility of plastics and polymer composites and the aesthetic possibilities when designing today's vehicles. In addition, many plastic resins are recyclable.