Evaluating Mechanical Properties of Cement Materials by Depth-Sensing Indentation Method

2010 ◽  
Vol 44-47 ◽  
pp. 2587-2591
Author(s):  
Xiu Fang Wang ◽  
Yi Wang Bao ◽  
Kun Ming Li ◽  
Yan Qiu ◽  
Xiao Gen Liu
Keyword(s):  
Mechanical Properties ◽  
Elastic Modulus ◽  
Energy Dissipation ◽  
Engineering Application ◽  
Calculated Data ◽  
Absorption Capacity ◽  
Cement Industry ◽  
Depth Sensing ◽  
Indentation Method ◽  
Recovery Resistance

The energy consumption of crushing is directly affected by the mechanical properties of cement materials. The elastic modulus, energy dissipation, recovery resistance and other mechanical properties of cement materials are evaluated based on the depth-sensing indentation method in this work. It is significant and efficient for engineering application. In results, the calculated elastic modulus is close to that measured by dynamic method, being used to verify the correctness of the calculated data. And the calculated energy dissipation of clinker is higher than that of limestone and granite, which can partially be used to explain why the grinding of clinker consumes a lot of energy in cement industry. The recovery resistance of clinker is almost identical to that of granite, more than that of limestone. It is found that the clinker, in contrast to granite and limestone, exhibits better plasticity and greater energy absorption capacity.

Study on Mechanical Properties of Cement Clinker and Limestone by Hertzian Indentation Method

2013 ◽  
Vol 302 ◽  
pp. 395-400
Author(s):  
Xiu Fang Wang
Keyword(s):  
Mechanical Properties ◽  
Energy Dissipation ◽  
Peak Load ◽  
Engineering Application ◽  
Absorption Capacity ◽  
Cement Industry ◽  
Cement Clinker ◽  
Indentation Method ◽  
Hertzian Indentation ◽  
Recovery Resistance

The recovery resistance, energy dissipation, and other mechanical properties of cement materials are evaluated based on the Hertzian indentation method in this work. It is significant and efficient for engineering application. In results, the calculated energy dissipation of clinker is higher than that of limestone, which can partially be used to explain why the grinding of clinker consumes a lot of energy in cement industry. The recovery resistance for limestone under the peak load of 100N is almost higher than of clinker. However, in contrast to that of 200N, the recovery resistance for limestone is almost identical to that of clinker. It is indicated that the clinker exhibits better plasticity. and greater energy absorption capacity.

Estimating Energy Dissipation of Ceramics via H-E Ratio

2010 ◽  
Vol 434-435 ◽  
pp. 205-208
Author(s):  
Yi Wang Bao ◽  
De Tian Wan ◽  
Yan Qiu
Keyword(s):  
Mechanical Properties ◽  
Elastic Modulus ◽  
Energy Dissipation ◽  
Elastic Recovery ◽  
Engineering Application ◽  
Basic Data ◽  
Recovery Resistance ◽  
Reduced Modulus ◽  
Energy Dissipation Capacity

Mechanical properties of ceramics are important for its engineering application. It would be significant and efficient if some properties could be estimated without tests. Energy dissipation capacity of ceramics is estimated in this work via two common parameters, hardness and elastic modulus, which could be obtained from basic data of commercial ceramics or simple tests. The ratio of hardness to reduced modulus H/Er is found to be related to recovery resistance and energy dissipation capacity of the materials, and the related equations were induced. The reduced modulus can be expressed by conventional elastic modulus E. Thus, the capacity of energy dissipation and elastic recovery can be estimated simply from the H/E ratio. The calculated results indicate that the value of H/E ratio is in reverse proportion to the energy dissipation. Several ceramics with different H/E ratio are analyzed and their energy dissipation capacities are estimated.

scholarly journals Experimental and Numerical Analysis of the Mechanical Properties of a Pretreated Shape Memory Alloy Wire in a Self-Centering Steel Brace

Processes ◽  
2021 ◽  
Vol 9 (1) ◽  
pp. 80
Author(s):  
Bo Zhang ◽  
Sizhi Zeng ◽  
Fenghua Tang ◽  
Shujun Hu ◽  
Qiang Zhou ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Elastic Modulus ◽  
Energy Dissipation ◽  
Shape Memory Alloy ◽  
Shape Memory ◽  
Loading Rate ◽  
Effective Elastic Modulus ◽  
Maximum Energy ◽  
Numerical Results ◽  
Energy Dissipation Capacity

As a stimulus-sensitive material, the difference in composition, fabrication process, and influencing factors will have a great effect on the mechanical properties of a superelastic Ni-Ti shape memory alloy (SMA) wire, so the seismic performance of the self-centering steel brace with SMA wires may not be accurately obtained. In this paper, the cyclic tensile tests of a kind of SMA wire with a 1 mm diameter and special element composition were tested under multi-working conditions, which were pretreated by first tensioning to the 0.06 strain amplitude for 40 cycles, so the mechanical properties of the pretreated SMA wires can be simulated in detail. The accuracy of the numerical results with the improved model of Graesser’s theory was verified by a comparison to the experimental results. The experimental results show that the number of cycles has no significant effect on the mechanical properties of SMA wires after a certain number of cyclic tensile training. With the loading rate increasing, the pinch effect of the hysteresis curves will be enlarged, while the effective elastic modulus and slope of the transformation stresses in the process of loading and unloading are also increased, and the maximum energy dissipation capacity of the SMA wires appears at a loading rate of 0.675 mm/s. Moreover, with the initial strain increasing, the slope of the transformation stresses in the process of loading is increased, while the effective elastic modulus and slope of the transformation stresses in the process of unloading are decreased, and the maximum energy dissipation capacity appears at the initial strain of 0.0075. In addition, a good agreement between the test and numerical results is obtained by comparing with the hysteresis curves and energy dissipation values, so the numerical model is useful to predict the stress–strain relations at different stages. The test and numerical results will also provide a basis for the design of corresponding self-centering steel dampers.

Mechanical Properties of Porous Si3N4 Ceramics

2013 ◽  
Vol 586 ◽  
pp. 166-169 ◽  
Author(s):  
Monika Kašiarová ◽  
Zuzana Vilčeková ◽  
Katarína Bodišová ◽  
Magdaléna Domanická ◽  
Miroslav Hnatko ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Elastic Modulus ◽  
Silicon Nitride ◽  
Porous Silicon ◽  
Trabecular Bone ◽  
Porous Ceramics ◽  
Porous Si ◽  
Depth Sensing ◽  
Bone Material ◽  
Polyurethane Sponge

Mechanical properties of porous silicon nitride prepared by two different processing routes have been studied. Depth sensing methods was used to measure the hardness and elastic modulus of experimental materials. The results were compared with the hardness and elastic modulus of trabecular bone in order to find out porous ceramics with properties close to that of trabecular bone. Material prepared by infiltration of polyurethane sponge exhibited properties close to the properties of bone and it is the potential material for further investigation in the bioapplication field.

Disclosing the Mechanical Properties of Green Calcium-Silicate-Hydrates by Statistical Nanoindentation Techniques

2011 ◽  
Vol 409 ◽  
pp. 544-549 ◽  
Author(s):  
Luca Sorelli ◽  
Daniel Vallée ◽  
Aali R. Alizadeh ◽  
James Beaudoin ◽  
Nicholas Randall
Keyword(s):  
Mechanical Properties ◽  
Elastic Modulus ◽  
Statistical Analysis ◽  
Calcium Silicate ◽  
Layer Structure ◽  
Cement Industry ◽  
Stoichiometric Ratio ◽  
New Class ◽  
Preliminary Work ◽  
Calcium Silicate Hydrates

In order to reduce CO2emissions, the cement industry has developed a new class cements. The Calcium-Silicate-Hydrates (CSH) that form are generally characterized by a low stoichiometric ratio for CaO and SiO2. This low C/S ratio affects the C-S-H layer structure and has a significant effect on the mechanical properties. This work exploits a novel statistical nanoindentation technique (SNT) to study the effect of the C/S ratio on the mechanical properties of synthetic CSH. Different CSH types were prepared by varying the C/S ratio of the starting materials. After undertaking a grid nanoindentation approach for each sample, the statistical analysis allowed extracting the mechanical properties, such as elastic modulus, hardness and creep. The results of this preliminary work shed new light on the implications of C-S-H stoichiometry on mechanical properties.

Surface Layer Micro-Hardness of Modified LDPE by Radiation Cross-Linking after Temperature Load

2015 ◽  
Vol 662 ◽  
pp. 177-180 ◽  
Author(s):  
Ales Mizera ◽  
Miroslav Manas ◽  
David Manas ◽  
Martin Ovsik ◽  
Martina Kaszonyiová ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Surface Layer ◽  
Cross Linking ◽  
Indentation Hardness ◽  
Micro Hardness ◽  
Depth Sensing ◽  
Indentation Method ◽  
Temperature Load ◽  
Irradiation Process ◽  
Different Doses

The presented article deals with the research of surface layer ́s micro-mechanical properties of modified LDPE by radiation cross-linking after temperature load. These micro-mechanical properties were measured by the DSI (Depth Sensing Indentation) method on samples which were non-irradiated and irradiated by different doses of the β – radiation and then were temperature loaded. The purpose of the article is to consider to what extent the irradiation process influences the resulting micro-mechanical properties measured by the DSI method. The LDPE tested showed significant changes of indentation hardness and modulus after temperature load.

A method of monitoring water absorption in polymers using a depth sensing indentation system

1996 ◽  
Vol 11 (2) ◽  
pp. 529-536 ◽  
Author(s):  
I. A. Ashcroft ◽  
G. M. Spinks
Keyword(s):  
Mechanical Properties ◽  
Elastic Modulus ◽  
Water Absorption ◽  
Creep Strain ◽  
Epoxy Adhesive ◽  
Depth Sensing ◽  
Surface Layers ◽  
Depth Profiles ◽  
Hardness Depth

The mechanical properties of many polymers are known to change as they absorb water. This fact has been used to monitor the absorption of water into the surface layers of an epoxy adhesive with a depth sensing indentation system. Two methods have been demonstrated. The sample can be immersed in water for a period of time and then removed and tested in air. Alternatively, the sample can be tested in in situ. In the second method the transport of water through the adhesive can clearly be seen in hardness/depth profiles. Hardness, elastic modulus, and creep strain of the adhesive change with time until a stable value is reached, which corresponds to full plasticization of the adhesive to the influence depth of the indenter. The initial mechanical properties of the epoxy are mostly recovered on drying.

Experimental Study on Mechanical Properties of Large NiTi Superelastic Shape Memory Alloy Bars

2021 ◽  
Author(s):  
Qiujun Ning ◽  
Lihua Zhu ◽  
Wei Han ◽  
Cheng Zhao
Keyword(s):  
Mechanical Properties ◽  
Energy Dissipation ◽  
Shape Memory Alloy ◽  
Shape Memory ◽  
Mechanical Performance ◽  
Engineering Application ◽  
Test Results ◽  
Equivalent Viscous Damping ◽  
Heat Treated ◽  
Strength And Stiffness

Abstract This study intensively examined the mechanical properties of large-sized superelastic shape memory alloy (SMA) bars, mainly focusing on their self-centering and energy dissipation capabilities. A detailed investigation on the effects of the heat treatment strategy, loading rate, strain amplitude, cyclic loading, prestress, and diameter of the SMA bars on their mechanical performance—residual strain, energy dissipation, equivalent viscous damping ratios, strength, and stiffness—was conducted. Furthermore, the fracture microstructure of monotonic tensile specimens was analyzed via scanning electron microscopy. The results indicated that the optimally heat-treated SMA bars show good superelasticity. The mechanical properties were relatively stable under constant strain loading–unloading training, which should be considered in engineering applications. The test results provided basic experimental data support for the engineering application of large SMA bars.

Characterization of the Mechanical Properties of Spring Materials

1974 ◽  
Vol 96 (3) ◽  
pp. 839-844 ◽  
Author(s):  
G. F. Weissmann ◽  
B. C. Wonsiewicz
Keyword(s):  
Mechanical Properties ◽  
Quality Control ◽  
Tensile Strength ◽  
Elastic Modulus ◽  
Energy Dissipation ◽  
Yield Strength ◽  
Tensile Testing ◽  
Control Applications

Spring materials are purchased under specifications which impose limits on the tensile strength but do not control the crucial properties, i.e., resistance to plastic flow and stiffness. Present techniques for characterizing spring material are discussed in detail. A novel test is described which is quick, inexpensive, and reliable and holds promise for both research and quality control applications. The test is based on a dynamic determination of energy dissipation in a sample stressed in bending or torsion, the usual modes of deformation for most springs. Stiffness and permissible deformations are determined directly and the elastic modulus and yield strength can be calculated easily. The results obtained in this way compare favorably with those determined by tensile testing. An example is given which illustrates the operation of the test and the calculation of results. Since the entire test from sample preparation to calculation of results requires about five minutes, and since the apparatus should be relatively inexpensive, the test ought to find application in many areas where testing is not practical at the present time.

scholarly journals Manufacture and Characterization of Biofoam Based On Composite of Taro Leaves Powder Reinforced Polyvinyl Acetate

2019 ◽  
pp. 141-148
Author(s):  
Arini Ulfah M.R ◽  
Syahrul Humaidi ◽  
Kurnia Sembiring
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Thermal Properties ◽  
Elastic Modulus ◽  
Water Absorption ◽  
Food Packaging ◽  
Raw Materials ◽  
Absorption Capacity ◽  
Third Stage ◽  
Leaf Powder

Biofoam material has been made for application of styrofoam substitute food packaging material from a mixture of raw materials: taro leaf powder and PVAc through a hot compaction method with variations of the composition of taro leaf powder: PVAc (80:20)% wt, (75:25)% wt, (70 : 30)% wt, (65:35) wt%, (60:40) wt%, (55:45)% wt, (50:50)% wt and (45:50)% wt. The first stage of taro leaves was blended and sifted with 100 mesh particle size. The second stage of the leaf powder of taro mixed with wet mixing was then mixed with PVAc as a matrix. The third stage of the homogeneous mixture was then put into the mold then compressed by heat to make it more dense with a pressure of 100 MPa and held for 10 minutes at 60 oC. Each biofoam sample that is ready to be characterized includes: physical properties (density, water absorption, functional groups and biodegredability), mechanical properties (tensile strength, elastic modulus, and elongation) and thermal properties (melting points). The characterization results showed that taro leaf powder: the optimum PVAc was (45: 55) wt% with a density value of 0.744 x 103 kg/m3, water absorption capacity of 1.765%, composed of OH and CH groups of PVAc and cellulose and C = C groups of lignin so that it has degrading properties of 91.2% for 50 days. Mechanical properties with tensile strength of 0.357 MPa, elastic modulus of 1.449 MPa, and elongation of 246.416%. Thermal properties with a melting point of 350.21 oC whose results have met the standards of conventional brand Synbra Technology. The results of biofoam material based on composite taro leaves and PVAc can be applied as food packaging.

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