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The literature [4] investigated the heat bending process of the wrought magnesium alloy AM30 by the experiments, and the results suggested moderate temperature, lower bending velocity and small original grain size are beneficial to the reduction of maximum wall-thinning rate, cross-section ovality and released spring back rate.
Table 1 Ф50×1×R75mm bending tool parameters Tool Groove dimensions (mm) Length dimensions (mm) Note (mm) Bend die 50 150（straight segment） bending radius 75 Clamp die 50 150 Pressure die 50 250 Wiper 50 128 Mandrel 47.6 202 mandrel extension length 6.5 Balls 47.6 18 (thickness) number 3 Take all factors including wall thinning, wall thickening, wrinkling, cross-sectional distortion multiple indices into consideration, the simulation results shows that, the reasonable bending velocity is 0.4rad/s, the matched pressure die velocity is 80%-110%.

In AHSS family, CP steels have a multiphase microstructure consisting of ferrite, bainite, small amount of martensite, and with large number of fine precipitates.
All the samples show very fine grain size characteristics.

The same sand type, with a maximum grain size of 0.3 mm, was used for all mix proportions.
There were 6 specimens cast for each considered case leading to a total number of 180 prisms.

As the Table 3 shown that the compressive strength of sandstone mainly depends on the mineral characteristics of the composition, particle size, porosity, cementing material species and moisture content.When the deposit law, the composition and the types of cementing material are basically the same, the compressive strength of fine-grained level sandstone is higher than coarse sandstone.
Table 3 The compressive strength test results of sandstone in different water state Sandstone origin Average compressive strength of sandstone (MPa) Softening coefficient Drying Air-dry Saturation West hill 53.5 38.9 284 0.53 East hill 108.1 62.7 46.3 0.43 Wulabo 117.5 82.3 604 0.51 Shibanliang 100.6 83.0 654 0.65 Table 4 The average strength, standard deviation and variation coefficient in different water state Sandstone state Average strength value (MPa) Standard deviation (MPa) Variation coefficient Group number (Each group of three pieces of specimens) Saturation 28.4 4.9 0.17 18 Air-dry 38.9 12.1 0.31 15 Drying 53.5 7.7 0.14 17 Tensile, Bending and Shearing Strength.

It is required that the dry powders present excellent flowability, reasonable grain size distribution (usually as an approximately normal distribution), specific water content (usually 5–7 wt.%), and uniform blending of raw materials [2].
Clearly, granule morphology is crucial in dry pressing operations since strongly influences particle packing during compaction and, thus, the size and number of pores in the green compact.

Table1 Corresponding strain rate of various fluctuate load parameters of the F-SSRT Numbers Reference speed (mm/s) Strain rate (s-1) Frequency (Hz) Fluctuation range (mm/s) Potential (mVSCE) 1 1.0×10-5 4×10-7 2.0×10-4 ±0.5×10-5 -850 2 1.5×10-5 6×10-7 2.0×10-4 ±0.5×10-5 -850 3 2.0×10-5 8×10-7 2.0×10-4 ±0.5×10-5 -850 4 2.5×10-5 1×10-6 2.0×10-4 ±0.5×10-5 -850 5 3.0×10-5 1.2×10-6 2.0×10-4 ±0.5×10-5 -850 Test results and analysis Fluctuant frequency's influence to SCC sensitivity of samples.Welding joint includes weld area, heat affected zone(HAZ) and base metal area.
The metal of overheated zone and protection film form galvanic corrosion cell, electrochemical corrosion reactions cause minimal initial crack on metal surfaces, promote the crack tip continuous dissolution, development, until the final material instability fracture.At the time of welding, overheated zone metal is in local melting state, and its grain is very coarse and uneven thickness, chemical composition is very uneven, the microstructure and composition are in extremely unbalanced state.

With the increase of loading direction angle θ, higher driving force is needed to enable martensite transformation in retained austenite grains[9].
Acknowledgments This work was supported by Guangdong provincial natural science foundation of china through grant number 2016A030313519.

There are a large number of variants that are equivalent in terms of ensuring the production of all areas with the required properties.
Corresponding Author Peter Monka, peter.monka@tuke.sk, +421 903 353 783 References [1] Goban, J. et al.: The numerical and computer aided confrontation of kinematic analysis of mechanism, In: Progressivnye technologii i sistemy masinostrojenija: mezdunarodnyj sbornik naucnych trudov, vypusk 41, Doneck, (2011), p. 15-20 [2] Panda, A., Jurko, J.: Replacement technology bevelling cage suitable technology, In: Ecology of borderland, Gorzów: IBEN, (2008), p. 197-200 [3] Valicek, J., Cep, R., Rokosz, K. et al.: New way to take control of a structural grain size in the formation of nanomaterials by extrusion, Material wissenschaft und werkstofftechnik, Vol. 43,   Issue 5,   Special Issue: SI, (2012), p. 405-411    [4] Kadnar M. et al.: The design and verification of experimental machine for real journal bearing testing, Technical Gazette, Vol. 18, n.1, (2011), p.95-98 [5] Knapcikova, L. et al.: Utilization of computer simulation at the selecting of optimal finishing method, In: ATP Journal

To overcome the wear of electrode tool, different researchers have proposed solution that consists in using a method of uniform wear method realized by a layer-by-layer machining [8] or using a high number of electrodes for roughing, semi-finishing and, respectively for finishing [1].
This could be explained by large grain size of the graphite which is inappropriate.

At the temperature of 740°C, in addition to the high level of spheroidization, it is also noticed the increase of the grain size, which contributes to the reduction of the hardness of the steel, compared to the samples treated at lower temperatures.
In the later stages of the process (times greater than 50 hours), the spheroidization process is basically in the stage of particle coalescing, thus reducing the number of particles of isolated carbides [7].