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If the cooling is slow, precipitates or second phases will form heterogeneously on dislocations or grain boundaries during cooling, which results in a reduction in supersaturation and concomitantly a lower strength after ageing.
The decrease in supersaturation of solute elements and vacancies with decreasing quench rate leads to a lower number density of precipitates, see complementary data in Fig. 5.

Key performance parameters To understand the operating conditions in the superstructure region of an Al melt-hold furnace in more detail, we worked with a number of Al producers.
Abrasion Resistance Test (ASTM C704); Samples pre-fired to 815°C are blasted with a stream of SiC grit of specified grain size for a set time.

Furthermore, the grain size for coarser particles is more significant.
A number ofdeep grooves and bigger wear debris and broken particles are seen on thesurfaces.

The filling material, consisting of 4¸8mm grain size gravel with 12.5kN/m3 weight, was set up to a height of 100mm in crown.
DIC is a full-field contactless optical method based on the correlation of the digital images taken during test execution that allows a large number of points to be monitored and provides the displacement and strain field of the specimen surface, reducing the cost and the time related to the installation of contact devices [14].

μ= 265p*rm*L-0.206p*rm (1) where: μ: friction coeffcient, p: mass applied on the samples (kg), rm: average radius of the wear track (cm), L: length of braking (mm); u=103 A*hE*N 2 where: u: specific wear (cm3/10-6 kg*m), A: contact area (cm2), E: kinetic energy of the apparatus (J), h: reduction of the depth of the sample tested (mm), N: number of braking.
Because of the different nature of the powders the pressure compresses and deforms differently the powder grains depending on their hardness.

In particular, a certain number of protectors after the drilling cycle do not have traces of contact with the walls of the well at all.
Before the test, the samples in the device shall be rubbed on a paper-based grinding skin with a low-grain electrocorundum (Fig. 7) until the samples are fully fitted to its abrasive surface.

Table 4 presents the simulation results and experiments that clearly demonstrate that these ratios are very useful and it is not required to make an excessive number of tests to validate the simulation.
[8]J.B.Leblond and J.C.Devaux,A new kinetic model for anisothermal transformation metallurgical transformations in steel including effect of austenite grain size, Acta Met., No.32, 1, p.146, 1984

However, knowledge from macro-scale part production cannot be directly applied to micro-scale processes due to scaling effects of grain to thickness ratio in sheet metal forming.
Table 1: Input parameters and material properties used for benchmarking of finite element analysis Case 1 Case 2 Case 3 Case 4 Targeted part shape Truncated cone shape with 45º wall angle ABAQUS\Explicit Material model Hardening Law Holloman type, isotropic Holloman type, isotropic Holloman type, isotropic Holloman type, isotropic Yield locus von Mises von Mises von Mises von Mises Element type Solid element with reduced integration Solid element with reduced integration Shell element with reduced integration Solid element with reduced integration and hourglass control Mass scaling factor 1.0E7 1.0E6 1.0E6 1.0E7 Friction condition Penalty, 0.1 Penalty, 0.1 Penalty, 0.1 Penalty, 0.1 Total # of elements 209,450 (5 in t0) 209,450 (5 in t0) 47,277 209,450 (5 in t0) Number of CPUs 108 108 72 108 CPU time HH:MM:SS 40:41:47 102:00:30 77:40:15 29:38:05 Effect of mass scaling: First two cases are meshed using C3D8R 8-noded solid elements with 209,450 elements.

. × Edge length [mm] Tool materials Coating type Number of teeth Helix angle [°] general end mill Φ6×15 6%Co，other WC Ultrafine diamond coating 4 40(right) cross-flute router Φ6×15 6%Co，other WC Ultrafine diamond coating 2 25(left), 25(right) fine-cross-nick router Φ6×15 6%Co，other WC Ultrafine diamond coating 12 40(left), 15(right) The milling experiment was carried out on QP2033-L VMC, and knife handle was BT40-KMC32-105.
It can be seen that ultrafine grain diamond coating grow well, compact structure before machining.

It is the self-consolidating fine grain concrete without any reinforced fibres.
Numbers around the crack (b), (c) represent debonding just after the first crack initiation.