دانلود کتاب،مقاله،جزوه و نرم افزار مهندسی مواد
کلیه منابع مورد نیاز دانشجویان و مهندسین مواد (متالورژی ، سرامیک ، جوش ، خوردگی ، نانو و بایومواد)دانلود کتاب،مقاله،جزوه و نرم افزار مهندسی مواد
کلیه منابع مورد نیاز دانشجویان و مهندسین مواد (متالورژی ، سرامیک ، جوش ، خوردگی ، نانو و بایومواد)بهبود یک فولاد میکروآلیاژی HSLA با وانادیم و تیتانیم
Effect of vanadium and titanium modification on the microstructure and
mechanical properties of a microalloyed HSLA steel
اثر بهبود یک‌نوع فولاد میکروآلیاژی HSLA با وانادیم و تیتانیم بر ریزساختار و خواص مکانیکی آن
ABSTRACT
Microalloyed high-strength low-alloy (HSLA) steels are essentially low carbon low-alloy steels that contain small additions (0.001–0.1wt.%) of alloying elements such as Nb, V, or Ti. These steels exhibit an outstanding combination of high strength, resistance to brittle fracture and good weldability, particularly if the carbon content is kept below ∼0.1wt.% . Several categories of HSLA steels have been developed catering to the needs of specific applications, such as the construction of large ships, oil and gas transmission lines, and offshore oil drilling platforms.
فولادهای میکروآلیاژی وانادیوم-نیوبیوم vanadium-niobium microalloyed steels
As-cast mechanical properties of vanadium/niobium microalloyed steels
خواص مکانیکی فولادهای میکروآلیاژی وانادیوم/نیوبیوم
ABSTRACT
Tensile and room temperature Charpy V-notch impact tests along with microstructural studies were used to evaluate the variations in the as-cast mechanical properties of low-carbon steels with and without vanadium and niobium. Tensile test results indicate that good combinations of strength and ductility can be achieved by microalloying additions. While the yield strength and UTS increase up to respectively 370–380 and 540–580 MPa in the microalloyed heats, their total elongation range from 20 to 25%. TEM studies revealed that random and interphase fine-scale microalloy precipitates play a major role in the strengthening of the microalloyed heats. On the other hand, microalloying additions significantly decreased the impact energy and led to the dominance of cleavage facets on the fracture surfaces. It seems that heterogeneous nucleation of microalloy carbonitrides on dislocations along with coarse ferrite grains and pearlite colonies trigger the brittle fracture in the microalloyed heats.