Why do we study materials? Many an applied scientist or engineer, whether me-
chanical, civil, chemical, or electrical, will at one time or another be exposed to a
design problem involving materials. Examples might include a transmission gear,
the superstructure for a building, an oil refinery component, or an integrated circuit
chip. Of course, materials scientists and engineers are specialists who are totally
involved in the investigation and design of materials.
Many times, a materials problem is one of selecting the right material from the
many thousands that are available. There are several criteria on which the final
decision is normally based. First of all, the in-service conditions must be character-
ized, for these will dictate the properties required of the material. On only rare
occasions does a material possess the maximum or ideal combination of properties.
Thus, it may be necessary to trade off one characteristic for another.The classic ex-
ample involves strength and ductility; normally, a material having a high strength
will have only a limited ductility. In such cases a reasonable compromise between
two or more properties may be necessary.
A second selection consideration is any deterioration of material properties that
may occur during service operation. For example, significant reductions in mechanical
strength may result from exposure to elevated temperatures or corrosive environments.
Finally, probably the overriding consideration is that of economics:What will
the finished product cost? A material may be found that has the ideal set of prop-
erties but is prohibitively expensive. Here again, some compromise is inevitable.
The cost of a finished piece also includes any expense incurred during fabrication
to produce the desired shape.
The more familiar an engineer or scientist is with the various characteristics
and structure–property relationships, as well as processing techniques of materials,
the more proficient and confident he or she will be to make judicious materials
choices based on these criteria
Results (
Arabic) 1:
[Copy]Copied!
Why do we study materials? Many an applied scientist or engineer, whether me-chanical, civil, chemical, or electrical, will at one time or another be exposed to adesign problem involving materials. Examples might include a transmission gear,the superstructure for a building, an oil refinery component, or an integrated circuitchip. Of course, materials scientists and engineers are specialists who are totallyinvolved in the investigation and design of materials.Many times, a materials problem is one of selecting the right material from themany thousands that are available. There are several criteria on which the finaldecision is normally based. First of all, the in-service conditions must be character-ized, for these will dictate the properties required of the material. On only rareoccasions does a material possess the maximum or ideal combination of properties.Thus, it may be necessary to trade off one characteristic for another.The classic ex-ample involves strength and ductility; normally, a material having a high strengthwill have only a limited ductility. In such cases a reasonable compromise betweentwo or more properties may be necessary.A second selection consideration is any deterioration of material properties thatmay occur during service operation. For example, significant reductions in mechanicalstrength may result from exposure to elevated temperatures or corrosive environments.وأخيراً، ربما النظر في الغالب أن الاقتصاد: ما سوفتكلفة المنتج النهائي؟ مادة ويمكن الاطلاع على أن لديه مجموعة مثالية من سند-آرتيس ولكن باهظ التكلفة. هنا مرة أخرى، بعض التوفيق أمر لا مفر منه.وتشمل التكلفة قطعة الانتهاء أيضا أي المصروفات المتكبدة أثناء التصنيعلإنتاج بالشكل المرغوب.أكثر دراية مهندس أو عالم مع خصائص مختلفةوعلاقات الملكية – الهيكل، فضلا عن تقنيات تجهيز المواد،أكثر كفاءة وثقة بأنه أو أنها سوف تكون لجعل المواد الحكيمالخيارات على أساس هذه المعايير
Being translated, please wait..
![](//wwwimg.ilovetranslation.com/pic/loading_3.gif?v=b9814dd30c1d7c59_8619)