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Examination of relationships among control and response FSW process variables (respectively e.g. tool rotation rate and torque) and weld microstructure and properties can provide important insight regarding how weld properties develop and how best to approach process development for different alloy classes.
Introduction The microstructure and consequent property distributions produced during FSW of aluminum alloys are dependent on several factors.
The contributing factors include: (1) Alloy composition, (2) alloy temper, (3) welding parameters, (4) gage of the welded plate and other geometric factors.
Plate gage and other geometric factors (e.g. shoulder size, heat sinks associated with clamping, etc.) may affect the temperature distribution within the weld zone and, in particular, through the thickness of the welded plates.
If the starting temper of the alloy is O, then the properties in the weld region will be similar to those in the base metal.

Creep Properties of P92 Pipe Weld after Annealing at 600 and 650˚C Karol Sówka1,a*, Hanna Purzyńska1,b, Adam Zieliński1,c, Marek Sroka2,d, Krzysztof Kwieciński1,e 1Lukasiewicz Research Network – Upper Silesian Institute of Technology, Gliwice, 44-100, Poland 2Silesian University of Technology, Faculty of Mechanical Engineering, Department of Engineering Materials and Biomaterials, Poland, Gliwice, 44-100, Poland.
This advanced creep-resistant steel demonstrates superior mechanical properties, including exceptional high-temperature strength retention, oxidation resistance, and creep rupture strength under prolonged thermal exposure.
These joints exhibit enhanced susceptibility to microstructural degradation and mechanical properties deterioration, particularly within the heat-affected zone (HAZ), during extended high-temperature operation.
Annealing resulted in significant creep rate acceleration compared to initial state conditions: at 600°C annealing temperature, creep rates increased by factors of 2.57 and 2.63 after 3,000 and 10,000 hours respectively.
For joints annealed at 650°C, creep rates increased by factors of 4.8 and 25.7 after 3,000 and 10,000 hours respectively.

In 1990s Japan, some European and American researchers on the basis of experimental and theoretical study of ordinary concrete, studied in-depth high strength, high-performance ceramisite concrete and achieved certain results, including the study of ceramisite concrete materials, configuration, production process, mechanical properties, and material properties and so on.
Testing methods: Many factors that affect the basic performance of ceramisite concrete, select the appropriate number of control factors.
Ceramisite concrete mixed with the right amount of Water-reducing can reduce the amount of cement to reduce the water-cement ratio, thus affecting the strength of ceramisite concrete.
(2) Water-cement ratio, sand ratio and Water-reducing admixture ratio are the important factors to affect the basic performance of ceramisite concrete.
Effect of expanded perlite aggregate on the properties of lightweight concrete.

Low-temperature cracking analysis of asphalt pavement LI Zhaoshenga, TAN Yiqiub School of Transportation Science and Engineering, Harbin Institute of Technology, Harbin 150090, P.R.China alizhaoshenghit@163.com, byiqiutan@163.com Keywords: asphalt pavement; low-temperature performance; temperature shrinkage coefficient Abstract: Establish the mechanical model of asphalt pavement low-temperature cracking, analysis the factors leading to cracking.
The factors such as shrinkage coefficient of asphalt pavement, temperature stress, pavement structure combination forms and temperature contribution affect the asphalt pavement on cracking behavior.
The paper analyzes the factors leading to cracking at low temperature and focuses on the effect of different aggregate gradation on temperature shrinkage coefficient.
Conclusion According to the energy method analyze the factors affect asphalt pavement on cracking at low temperature, the factors include the temperature shrinkage coefficient of asphalt mixture, temperature stress, the combination forms of the pavement structure and temperature distribution.
Analyze the effect of gradation on asphalt mixture properties of shrinkage at low temperature, for the same skeleton type, the smaller average grain diameter is, the larger shrinkage deformation of asphalt mixture is at low temperature; in order to improve the properties of asphalt mixture resistance to cracking, improving the coarse aggregate consumption can be adopted to form coarse skeleton dense structure and reduce the shrinkage coefficient at low temperature.

The mixtures were evaluated to determine several key responses that affect the fresh properties of precast, prestressed concrete, including filling ability, passing ability, filling capacity, surface settlement, and column segregation.
Five key mixture parameters were selected to derive statistical models to evaluate key properties of SCC.
All factors are expressed in terms of coded values.
The models are expressed as the factors with the highest influence on the modeled responses list by descending order.
J., Khayat, K.H., "Statistical Models to Predict Mechanical and Visco-Elastic Properties of SCC", Proceedings, 2nd International Symposium on Design, Performance and Use of Self-Consolidating Concrete, Beijing, China, June 5-7, 2009, pp 506-525

Friction stir processes (FSP) are important for enhancing mechanical properties of metal sheets, such as the tensile strength, the elongation, etc.
The stress distribution of the tool pin is affected by the thermo-mechanical characteristics of the workpiece in FSP.
The mechanical properties of a welded sheet material have various advantages such as improved strength, finer grain size, better fatigue strength and anti corrosion property.
The thermal-mechanical affect zone (TMAZ) and thermal affect zone (TAZ) occurred under the welding path, i.e. the rotating tool pin causes a TMAZ and TAZ.
Fratini used an inverse identification approach based on a linear regression procedure to develop the material properties.

Aside from these, the mechanical properties of natural fiber composite are surprisingly good.
The water absorption issue can also result in insufficient adhesive strength between matrix and fiber, thus affect the mechanical properties of the composite [8].
Aside of modifying the fiber surface, fiber loading is another factor which will affect the overall performance of the composite.
Effect of Different Surface Treatments on Mechanical Properties of the Composite.
However, mechanical properties of a composite can be weakened by improper surface treatment.

They found that the temperature dependence of the material properties affects the thermal buckling and postbuckling characteristic of symmetrically laminated beams.
The specimens were tested to measure the mechanical properties at various temperature levels; -20 to 70°C.
The safety factor for the whole HVAC system is smaller of the safety factors of lower and upper parts.
However, because the ultimate strength also decreases with temperature, the safety factors are 2.96 and 2.54 with temperature-dependent and constant materials properties, respectively.
Wang, Mechanical properties of foamed concrete exposed to high temperature, Vol. 26, No. 1 (2012) 638-654

The influence of sintering temperature on the mechanical properties of ceramics, especially cracking resistance, was studied.
The effect of the particle size of powders [10], porosity [11], and temperature [12] on the mechanical properties was studied.
Running-in is one of the important indicators of the tribological properties of materials, during which optimization of the micro geometry and physico-mechanical properties of the surface layers of the contacting materials occurs.
Mechanical properties of ceramic composition ZrO2-3 mol.% Y2O3.
Tribological parameters are influenced by three groups of factors: values that determine the level of external influence on the tribosystem: p - contact pressure, sliding speed, temperature; physical and mechanical properties of materials, of which the most important are the quantities that determine the properties of the surface layers of the contacting materials: elastic modulus E, hardness H, and for brittle materials such as ceramics - stress intensity factor K1c; micro geometry of friction surfaces.

The excellent mechanical properties (i.e., elongation of 52%, a tensile strength of 785 MPa) have been obtained by adjusting the volume fraction and the stability of austenite.
Nowadays, the Fe-Mn-Al-C low-density steels are fairly attractive for the automotive due to their excellent mechanical properties [3-5].
Therefore, it is necessary to design a proper mechanical stability of austenite for achieving better mechanical properties.
The 900-5 steel exhibits a good combination of mechanical properties, with a product of tensile strength and elongation of 40.9 GPa·%
Peng, Evolution of the microstructure and mechanical properties of an austenite-ferrite Fe-Mn-Al-C steel, Materials Science and Engineering A, 643 (2015) 183-193