نتایج جستجو برای: time dependent creep
تعداد نتایج: 2449530 فیلتر نتایج به سال:
Ultrahigh-performance concrete (UHPC) is a new class of concrete, differentiated from conventional by clear distinctions in its material behaviors. Understanding and managing time-dependent properties necessary for the appropriate use any concrete-like material. This study investigated suite commercially available UHPC-class materials, with goal being to characterize behaviors then propose pred...
In this study, a large number of creep tests were carried out to study the effect of stress level and testing temperature on the creep behavior of 63 Sn/37Pb solder in a systematic manner. Based on the dislocation controlled creep mechanism and Gibbs’ free-energy theory, a new creep constitutive model was proposed. The model was found to describe accurately the creep flow of the solder and to b...
Existing design guidelines for concrete hinges consider bending-induced tensile cracking, but the structural behavior is oversimplified to be time-independent. This is the motivation to study creep and bending-induced tensile cracking of initially monolithic concrete hinges systematically. Material tests on plain concrete specimens and structural tests on marginally reinforced concrete hinges a...
Nanoindentation has recently gained attention as a characterization technique for mechanical properties of biological tissues, such as bone, on the sub-micron level. However, optimal methods to characterize viscoelastic properties of bones are yet to be established. This study aimed to compare the time-dependent viscoelastic properties of bone tissue obtained with different nanoindentation meth...
The compressive creep and recovery of foam earplugs was studied at various applied stresses leading to different fi nal creep strains. Deformation was determined from digital videos of the earplugs via image processing software. Creep could not be modeled by a single exponential in time; creep approximated a power law in time. Nonlinear viscoelasticity was observed: creep compliance depends on ...
Tensile–creep experiments were conducted in the temperature range 100–200 C and stress range 20–83 MPa for a series of magnesium–zinc–yttrium (Mg-Zn-Y) and mangnesium-zinc–zirconium (Mg-ZnZr) alloys ranging from 0 to 5.4 wt% Zn, 0 to 3 wt% Y, and 0 to 0.6 wt.% Zr. The greatest tensile– creep resistance was exhibited by an Mg–4.1Zn–0.2Y alloy. The room-temperature yield strength increased with i...
در این پایان نامه در آغاز با بیان اهمیت مطالعه پلاسما با توجه به کاربردهای متعدد آن به معرفی ویژگی ها و روش های ایجاد اشعه ایکس از برهم کنش لیزر با پلاسما پرداخته ایم. سپس مدل های مختلف پلاسما و مدل های تعادلی آن معرفی شده است. از میان این مدل ها مدل تعادل ترمودینامیکی غیر موضعی nlte)) جهت بررسی انتخاب شده است. در این مدل با حل معادله آهنگ، جمعیت فازهای یونی مختلف را با تشکیل ماتریس آهنگ محاسبه...
Time dependent plastic deformation in metals can occur at high temperatures. Typically the creep test is conducted to characterize the deformation features; however, the conventional uniaxial power-law creep test may be impractical for small scale materials. Accordingly, instrumented indentation techniques are frequently employed. This study concerns the employment of instrumented indentation t...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید