In this article we will discuss about the mechanics of machining operation. And also learn about:- 1. Mechanism of Chip Formation 2. Mechanics of Chip Formation 3. Heat Generation and Cutting Tool Temperature 4. Failure of Cutting Tool and Tool Wear 5. Cutting Tool Materials 6. Tool Life and Machinability and 7. Cutting Fluids. Before we start our discussion on [...]
Guide for manufacturing and making Pig Iron. Following three distinct operations are involved in the manufacturing process of pig-iron: (1) Dressing (2) Calcination and roasting (3) Smelting. (1) Dressing: The iron ores as obtained from mines are crushed into pieces of size of 25 mm diameter. This is achieved in the rock crushers of ordinary type. The crushing of ores [...]
Following are the methods which are usually adopted to prevent the corrosion of ferrous metals: 1. Coal Tarring 2. Electroplatings 3. Embedding in Cement Concrete 4. Enamelling 5. Galvanizing 6. Metal Spraying 7. Painting 8. Parkersing 9. Sherardising 10. Tin Plating and Terne Plating. Method # 1. Coal Tarring: In this method, the iron is dipped in hot coal tar [...]
In this article we will discuss about:- 1. Meaning of Corrosion 2. Causes of Corrosion 3. Factors 4. Theories 5. Forms 6. Effect 7. Corrosion of Ferrous Metals 8. Corrosion of Non-Ferrous Metals 9. Standard Electrode Potential 10. Prevention of Corrosion of Steel in Concrete. Meaning of Corrosion: The term corrosion is defined as an act or process of gradual [...]
In this article we will discuss about:- 1. Manufacture of Cast-Iron 2. Composition of Cast-Iron 3. Types 4. Properties 5. Uses 6. Castings 7. Types of Castings 8. Characteristics of a Good Casting 9. Defects in Casting. Manufacture of Cast-Iron: The cast-iron is manufactured by re-melting pig-iron with coke and limestone. This re-melting is done in a furnace known as [...]
Griffith attributed the discrepancy between the observed fracture strength of crystals and the theoretical cohesive strength to the presences of flaws in brittle materials. This theory is applicable only to perfectly brittle material such as glass, and cannot be used directly to metals. However, Griffith's ideas formed a base to understand the fracture in metals. Griffith proposed that a brittle [...]
In this article we will discuss about:- 1. Introduction to Solid Solution of Metals 2. Types of Solid Solutions 3. Hume Rothery's Rules for Primary Substitutional Solid Solubility. Introduction to Solid Solution: When the liquid solution of two metals crystallises, and if a solid of only single crystal structure forms, then a solid solution has formed. This happens when atoms [...]
In this article we will discuss about:- 1. Introduction to Phase Diagram 2. Phase Rule 3. Prediction 4. Uses 5. Limitations. Introduction to Phase Diagram: As the properties of a material depends to a large extent on the number, amount, type and the form (shape and the size) of the phases present, and can be altered by changing these quantities, [...]
Pfann's technique of zone-refining has been applied to the purification of many metals, particularly silicon and germanium. The high purity silicon required for transistors for the electronic industry is produced by the concept of purification based on zone-refining. The concept is based on the non-equilibrium behaviour during solidification of the solid solution alloys. Purification of a metal by zone-melting (i.e., [...]
Quite a large number of phase diagrams of metal systems are available, but repeated investigations, with refinements in apparatus and techniques, lead to their frequent revision. No one method is best for all alloy systems, or even to locate all the boundaries in one alloy system. A diffusion couple is used to get the number and the order of the [...]