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Pictures of samples after heat treatment (750 ℃×5 h) Table 2 The linear change rate of sample after heat treatment (750 °C×5 h) sample number Lc /% R-MCr +0.27 R-HCr +2.27 R-ACr -10.9 Fig. 3.XRD pattern of samples after heat treatment (750 ℃×5 h) The SEM image of sample after reaction shows in Fig. 4, and micro-area molar compositions presents in Table 3.
Potash uniform distributes on the surface of magnesia-chrome spinel, locally generates MgO and K2CrO4 at the edge of grain, and shows less erosion by potash.
Part of the potash distributes on the surface of chrome-corundum, and grain morphology is incomplete, which shows the crystal have subjected to a greater degree of erosion.
Magnesia-chrome brick is mainly composed of solid-solution with magnesia and magnesia-chrome spinel grains and magnesia-chrome spinel matrix.
The edge sharpening of chromic oxide particles are weakened and a large number of potassium salts are deposited in chromic oxide, which shows that a greater extent of reaction between potassium and chromic oxide.

Introduction Isotropic graphite of high quality is characterized by its ultra fine grain, high density and high strength, which makes it gain the advantages over copper electrode in Electro-discharge machining (EDM) of dies and molds manufacturing by its lower electrode wear, quicker EDM productivity, better machinability, lighter weight, etc. [1].
In comparison with the conventional end milling, micro-end-milling has almost the Journal Title and Volume Number (to be inserted by the publisher) 859 same cutting force characteristics, but the wear mechanisms are very different.
As the graphite grains are ultra-fine and the cutting tool has a relatively larger edge radius, the material in the tool-work contact zone is crushed into fracture chips.
When the end mill moves forward in step (b), these fine � � � � � � � � � 10µµµµm Flake chips Clearance Face Journal Title and Volume Number (to be inserted by the publisher) 861 particles flow out of the tool edge under the crush action of the rake face, and the spheric chips are created and a main crack appears ahead of the tool tip towards the downward direction.
The project is guaranteed by Fifteenth Science & Technology Key Project of Guangdong Province (China). 50µ50µ50µ50µm (a) Flank wear 50µ50µ50µ50µm (c) Substrate Coating Flank wear 200µ200µ200µ200µm (b) 200µ200µ200µ200µm (d) 0.01 0.02 0.03 0.04 0.05 Flank Wear Area (mm )2 0 10 20 30 40 50 Cutting Length (m) Un-coated Coated Journal Title and Volume Number (to be inserted by the publisher) 863 References [1] Shanghai Toyo Tanso: Catalog of Graphite Material and Products No.

While being mixed in electromagnetic field, fine-grained particles of Portland cement and modifier were adsorbed on the surface of basalt fiber and magnetized metal fiber which served as structure-forming components; this resulted in a more efficient spatial distribution of fiber and enhancement of the mixture reactivity.
The following known data were used for the calculation: λ fc =2.0 W/(m×К) - thermal conductivity factor of dry fiber-reinforced concrete; λc.s. = 0.58 W / (m×K) - thermal conductivity factor of dry sand-cement mortar; nair = 3 - 9 pcs. - number of air spaces; dair = 0.005 m - thickness of air spaces.
At that, the distance from the air spaces to the edges of the block remains constant changing the thickness of the fiber reinforced concrete screens and their number change.
Perfilov, Fine-grained fiber reinforced concretes.
Zubova, Fine-grained basalt fiber reinforvced concrete, Bull. of the Volgograd St.

It results in the quenching surface with ultra-fine grained structures [13].
Sodium bicarbonate was chosen because it would assist to form a large number of hydrogen bubbles at the cathode.
A huge number of pores can be found on the surface of A0 (Figure 5a).
The number and size of the pores dramatically drop.
surface resulting in the ultra-fine grained structures [13].

In the Mini SIMS profile, the peak intensities of mass number 16 (-O-) and 17 (-OH) were increased after the chemical treatment.
The grain size of the Fig. 1 Various SEM morphologies of diamond films on Ti substrate after deposition; (a) sample 1, (b) sample 2, (c) sample 3 (a) (b) (c) polycrystalline diamond and the nanocrystalline diamond was approximately 1µm and 30nm-50nm, respectively.
In this study, the grain size of diamond was decreased with increasing CH4 concentration.
Fig. 4 FT-IR spectra of diamond films before the oxidization treatment; (a) sample 1, (b) sample 2, (c) sample 3 2800 2850 2900 2950 3000 Absorbance Wave number(cm -1) 1000 2000 3000 4000 Wave number(cm -1 ) Fig. 5 FT-IR spectra of sample 1 modified by the chemical treatment of case 1; (a) non hydrolysis treatment, (b) NaOH treatment, (c) HCl treatment.
After the NaOH treatment, the intensities of mass number 16 (O) and 17 (OH) increased.

Indoor tensile stress test of asphalt mixture Type of specimen Type of fiber Number of specimen type Test condition Test results (splitting strength/bending strength) MPa Standard Marshall specimen No fiber WMP15 15℃ Splitting test 1.83 Short-cut mineral fiber DMP15 1.88 Mineral cotton fiber KMP15 1.98 No fiber WMP25 25℃ Splitting test 0.95 Short-cut mineral fiber DMP25 1.01 Mineral cotton fiber KMP25 1.10 Trabecular specimen No fiber WLW-10 -10℃Trabecular bending test 0.47 Short-cut mineral fiber DLW-10 1.39 Mineral cotton fiber KLW-10 0.80 No fiber WLW20 20℃Trabecular bending test 0.66 Short-cut mineral fiber DLW20 0.55 Mineral cotton fiber KLW20 0.80 Test results show that adding fiber in asphalt mixture produce different influence of strength under different temperature conditions. splitting strength and bending strength of the AC16 under different temperature condition have big distinction, which is proof that the asphalt mixture has considerable temperature sensitivity
Asphalt mixture fracture morphology and fracture mechanism analysis AC mixture is a suspension close-grained structure, and its tectonic contains four basic parts, aggregate, aggregate - asphalt interface area, asphalt layer, asphalt mortar layer [14].The destruction of asphalt mixture firstly product in the weakest position, then crack propagation has two possible paths, namely the crack through aggregate extend along the original direction or crack deflection expand bypass aggregate cementing area, There are three kinds of destruction in the cement area, respectively is stone - asphalt binder interface degum damage, asphalt tack coat destruction, asphalt mortar layer destruction.
No fiber asphalt mixture section still distribute many honeycomb holes, adding mineral fiber asphalt mixture relatively close-grained, short- cut mineral fiber asphalt mixture section have fiber uproot and fiber knot regiment phenomenon, mineral cotton fiber asphalt mixture section have no fiber knot regiment phenomenon.
As Figure 3 shows, - 10℃ the trabecular bending test specimen section is flat, fracture contains the aggregate fracture, stone-asphalt interface degum damage, asphalt tack coat damage, as well as mortar layer damage; No fiber asphalt mixture section still distributes many honeycomb holes, and has few big aggregate crack about the fracture; Adding mineral fiber of asphalt mixture relative close-grained, fracture more smooth, cracks expansion through aggregate along the primary direction, rare bending phenomenon, specimens belong to brittle fracture; Mineral fiber asphalt mixture section can't see fiber uproot phenomenon, proof that fiber has also undergone a rupture.
No fiber asphalt mixture section still distributes many honeycomb holes, Adding mineral fiber of asphalt mixture relative close-grained, short- cut mineral fiber asphalt mixture section exists fiber uproot and knot regiment phenomenon, which serious impact the trabecular bending strength of the smaller size section, mineral cotton fiber asphalt mixture section has no fiber uproot phenomenon.

Special attention was focused on centerline segregate non-uniformity of the concast slabs, whose centerline unsoundness and centerline cracking number was not to not exceed 2 by the reference chart in OST 14-4-73 "Method of macrostructure examination in the cast billet (slab) manufactured by continuous casting".
Mechanical properties of 24, 27 and 31 mm plates, steel Х65 Shear area Plate thickness, [mm] Heat YS, [MPa] TS, [MPa] YS/ TS El(2"), [%] CVN -30 o C, [J] Charpy -30 oC ВDWTT -10 oC CTOD 0 oC, [mm] 1 565 493 0.87 29 278 100/100 95/95 0.55 24 2 565 492 0.87 30 225 100/100 95/95 0.50 3 565 499 0.88 29 217 100/100 95/95 0.49 27 4 550 488 0.88 30 236 100/100 95/95 0.49 5 540 469 0.87 28 146 100/100 95/95 0.40 31 6 551 483 0.88 32 167 100/100 95/95 0.39 Metallographic examination of X65 plates showed that metal structure in all thicknesses was the combination of fine grain ferrite with the average grain size 12 and perlite in the amount of 5-7 % (Fig. 1, а).
Significant grain refining is achieved by microalloying by bigger amount of niobium.
This element acts to restrain austenite grain growth during heating, retards recrystallization processes and increases the initial temperature of recrystallization thus extending the temperature region of non-recrystallized austenite existence during TMCP.
After tempering, fine recrystallized grains of ferrite with dispersed tempering carbides inside appeared in place of high carbon martensite.

However, more and more concrete buildings were removed and a large number of abandoned concrete has been presented due to the employment environmental effects in some projects, the hidden danger in the region of design or construction, the arrival of the usage limit and the renewal and remake of the city.
The physical mechanical properties of recycled aggregates blended by hand was shown in Table 1, conforming to the demands of the consecutive grain size distribution of (5~31.5) mm provided by Pebble and Crushed Stone for Building (GB/T14685-2001).
Meanwhile, the grain size of recycled aggregate crushed by crusher was mainly ranged from 9.5 mm to 26.5 mm.
The recycled aggregates with the grain size range of (9.5~19.0) mm were adopted for compounding pervious concrete.
Fine aggregate: Natural sand with the grain size range of (0.63~1.25) mm.

At present, the concrete applied in large number over the world is ordinary concrete.
Small grain stone may sedi- ment on the upside of underlayer coarse aggregate and water goes up to the underside of upper layer coarse aggregate and stop there motionlessly to form water sack.
For example, a crushed limestone with grain size of 5 to 30 mm, an apparent density of 2.65, an accumulated density of 1390 kg/m3, has a void ratio of P= (1-p0/p)*100%=(1-1.39/2.65)*100% = 47.5% (1) A type of pea gravel is of grain size of 5 to 10 mm, an apparent density of 2.62, an accumulated density of 1480 kg/m3.
**A kind of composite super-fine power Table2 Slump loss No. 0 hr 1 hr 2 hr 1 21.0 cm 21.0 cm 20.0 cm 2 21.0 cm 20.5 cm 20.0 cm Table3 The amount of bleeding [g/L] No. 30 min 60 min 90 min 120 min 1 2 4 10 12 2 0 0 0 0 Examples Take C40 for example, the mix proportion of ordinary concrete and performance-enhanced ordinary concrete is shown in Table 1, where cement is 525 # Portland cement of brand Taili; coarse aggregate is crushed limestone of grain size of 5 to 25 mm with an apparent density of 2.65, an accumulated density of 1320 kg/m3; the pea gravel is of grain size of 5 to10 mm with an apparent density of 2.56, an accumulated density of 1400 kg/m3; the sand has a fineness modulus of 2.6, an apparent density of 2.61, an accumulated density of 1500 kg/m3; the ultra-fine powder is a kind of composite one with a specific surface of 6000cm2/g,; the water-reducer, called FFDT, is a kind of composite mixture composed of naphthalene and non-naphthalene

It has been argued that the fact, that each segment of the material is considered as an isolated entity unable to interact with the others, could lead to ignorance of effect from the impingement of recrystallized grains from neighboring regions.
While 0.5t is a function of strain, strain rate( ε& ), initial grain size( 0D ) and temperature(T) in the case of static recrystallization and described by the following form that is well documented in the literatures [4,5,6], 0.5 0 0 exp( / ).
p n k C ε ⋅= ⋅ (6) where 1C is considered as a constant dependent on the initial grain size and temperature.
Results and Discussion Curves of log(ln(1/(1-XV))) vs. log(t) Figure 1 shows typical examples of the recrystallization kinetics as predicted for a number of relevant parameter values by Eq.(10).
This new model also predicts that high values of the Avrami exponents are only observed when the local strain variation is very small, such as in the case of lightly deformed, fine grained, texture free materials of a uniform grain size.