Eray Cavus 030060022 9th Week Part 3

TRIP Steels (Material)

TRIP Steels (old)

Trip steels represent a new , exciting materila being developed.Their microstructure consists of a continuous ferrite matrix and a dispersion of a harder second phase(martensite and/ or bainite).In addition . the microstructure consists of retained austenite.Trip steels exhibit better ductlilty and formability at a given strength level because of the transformation of retained austenite to martensite during plastic deformation.Transformation induced plasticity(TRIP) steels are useful for more complex shapes.

(The science and engineering of materials,Donald R. Askeland,Pradeep Prabhakar Phulé page 480 )

TRIP Steels (new) (better)

The steels developed to exploit the properties obtained when the martensite reaction occurs during plastic deformation are known as transformation-induced plasticity (TRIP) steels. They are strong and exhibit considerable uniform elongation before failure. There are several varieties of such steels. Thosse which are made fully austenitic by using large quantities of austenite-stabilizing solutes, but transform the martensite when stressed, are simply called the TRIP steels. When the austenite is a minor phase in the overall microstructure, but under goes martensitic transformation during straining, the steels are said to be TRIP assisted and are usually low alloy steels.

(Steels: Microstructure And Properties, Yazar: Harshad Kumar Dharamshi Hansraj Bhadeshia,Robert William Kerr Honeycombe, page:223)

Electrolysis (Manufacturing Method)

Electrolysis (old)

 The following remarks on electrolysis are intended simply as an aid to those who have to make an occasional electrolytic determination of copper, nickel, or bismuth is described, and a few general directions are given as to manipulation and the attainment of the proper conditions.

(Technical methods of ore analysis, Albert Howard Low.p.10)

Electrolysis (new)(better)

There are three classes of liquids:

1.    Nonconductors (insulators), such as oils and turpentine.

2.    Conductors, which pass electrical current without deterioration. Mercury and molten metals are examples.

3.    Those liquids that will decompose when conducting an electrical current. Dilute acids, solutions of metallic salts, and certain fused solidcompounds are of this kind.

TERMINOLOGY

The liquids of class 3 are of interst because the electricity is transferred through these liquids by carriers that are called ions. The liquid is called the electrolyte. The transfer of ions is termed electrolysis. The apparatus used is termed the electroytic cell. The plates immersed in the electrolyte, fort he purpose of current entry and exit, are termed electrodes.

The electrode through which the current enters the electrolyte is called cathode. The electrode through which the current leaves the electrolyte is called the anode. See Figure 9-1, which illustrates the nomenclature used with an electrolytic cell.

Chemistry of Electrolysis

The electrolyte will dissociate into positive(+) and negative (-) ions. The positive ions are attracted to the cathode and the negative ions are attracted to the anode. See Figure 9-2.

Water is usually used as the bas efor the electrolyte, with acids or metallic salts added to it. Hydrochloric acid (HCI) is often used as the additive to water (H₂O ) as the base. The hydrochloric acid dissociates into positive hydrogen ions and negative chloride ions. This may be written in the equation.

            HCL= H⁺  +  CL^-

See Figure 9-3. Ionization in no manner changes the properties of the atoms. Hydrogen ions, such as H⁺, will affect such chemical indicators as litmus paper, while hydrogen gas (H₂) won`t affect litmus.

(Audel Electrical Course for Apprentices and Journeymen,Yazar: Paul Rosenberg, page:111-112)