Type -3- Two metals, completely soluble in all proportion in the liquid state, are only partially soluble in the solid state
Since most metals show some solubility each other in the solid state, this type is the most common and therefore, the most important alloy system
Fig -10- Phases diagram illustrating partial solid solubility
The melting points of the two pure metals are indicated at points TA and TB, respectively. The liquidus line is TA E TB, and the solidus line is TA F E G TB. Above the liquidus line, there is only a single phase liquid solution. These metals (metal A and metal B) are partly soluble in the solid state, a solid solution must be formed. Alloys in this system never solidify crystal of pure A or pure B but always a solid solution or mixture of solid solutions. At TE, the solid solution dissolves a maximum of 20 % B as shown by point F, and the B solid solution a maximum of 10 % A as shown by point G. With decreasing temperature, the maximum amount of solute that can be dissolved decreasing, as indicated by lines FH and GJ. These lines are called solvus lines and indicate the maximum solubility (saturated solution) of B in A ( - solution) or A in B (B solution) as a function of temperature point E, where the liquidus lines meet at a minimum is known as the
(eutectic point).
Example
Draw cooling curve of alloy (1) (Fig. 10)
Fig -11- The cooling curve and microstructure at various temperature during solidification of 95 % A – 5 % B alloy
As example:
المادة المعروضة اعلاه هي مدخل الى المحاضرة المرفوعة بواسطة استاذ(ة) المادة . وقد تبدو لك غير متكاملة . حيث يضع استاذ المادة في بعض الاحيان فقط الجزء الاول من المحاضرة من اجل الاطلاع على ما ستقوم بتحميله لاحقا . في نظام التعليم الالكتروني نوفر هذه الخدمة لكي نبقيك على اطلاع حول محتوى الملف الذي ستقوم بتحميله .
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