Silicon Carbide Series
High Temperature Series
Item Code：A2503
So far, the main producing method of SiC refractory material combined with Si3N4 is reaction sintering.
The process principle is: adding a certain amount of Si powder into industrial SiC materials with a certain particle size (or mixing with SiO2 fine powder and Al2O3 fine powder), then mixing and moulding, and conducting reaction sintering at about 1450℃in a high purity atmosphere of N2. During sintering process, chemical reactions showed as follows:
3Si+2N2→Si3N4
3Si+SiO2+2N2→2Si2N2O
Si3N4+SiO2→2Si2N2O
The Si3N4 and a few amount of Si2N2O generated by reactions firmly combines SiC particles and brings excellent performance for the series.
Application
The series is mainly used for muffles furnace in glass industry. It also has abilities to be used in key parts of wear-resistant in furnace of industries in steel, petrochemical, non-ferrous metal, electronics, waste incineration, etc.Characteristics
The series has inherited lots of excellent properties from silicon nitride and silicon carbide materials.- High strength in both normal and high temperature conditions
- High thermal conductivity
- Low coefficient of linear expansion
- Good thermal shock resistance
- Excellent high temperature wear resistance
- Strong resistance to chemical erosion
Physical and Chemical Indicators
| Table 1: Physical and chemical indicators of nitride combined with refractory products | |||||||||||
| Item | Electrolytic aluminium | Steel | Ceramics | Synthetical industry | Single value allowable deviation during reinspection | ||||||
| L-DGT | T-DGT | T-SLT | T-SLG | Y-DGT | Y-DWT | Z-DWT | |||||
| AP/% | ≤ | 17 | 17 | 16 | 15 | 18 | 18 | 20 | +1 | ||
| BD/（g.cm3) | ≥ | 2.65 | 2.65 | 2.65 | 3.15 | 2.60 | 2.60 | 2.55 | -0.03 | ||
| CCS/Mpa | ≥ | 150 | 160 | 150 | 130 | 120 | 120 | 100 | -15 | ||
| Cold bending strength/Mpa | ≥ | 40 | 45 | ─ | ─ | 40 | 40 | 35 | -5 | ||
high temperature bending strength a | 1000℃ | ≥ | 42 | ─ | ─ | ─ | ─ | ─ | ─ | -5 | |
| 1350℃ | ≥ | ─ | 40 | 42 | 20 | ─ | ─ | ─ | -5 | ||
| 1400℃ | ≥ | 45 | 45 | 45 | 22 | 40 | 40 | 40 | -5 | ||
| Thermal Conductivity b (1000℃)/ [W/(m·K)] | ≥ | 16 | 16 | 15 | ─ | ─ | ─ | ─ | ─ | ||
| alkali resistance b（930℃×3h×2次）/% | ─ | ─ | ±5.0 | 0–＋5.0 | ─ | ─ | ─ | ─ | |||
| chemical component % | ω（SiC) | ≥ | 72 | 72 | 71 | ─ | 70 | 70 | 70 | -1 | |
| ω（Si3N4) | ≥ | 18 | 20 | ─ | ─ | 20 | ─ | ─ | -1 | ||
| ω（AL2O3） | ≥ | ─ | ─ | 5.0 | 80 | ─ | ─ | ─ | -1 | ||
| ω（N) | ≥ | ─ | ─ | 5.5 | 5.0 | ─ | 4.8 | 4.8 | -0.1 | ||
| ω（Fe2O3) | ≥ | 0.7 | 0.7 | 0.7 | 0.7 | 0.7 | 0.7 | 0.7 | +0.05 | ||
| ω（SiC+Si3N4) | ≥ | 94 | ─ | ─ | ─ | ─ | ─ | ─ | -1 | ||
| A. Test temperature shall be agreed upon by the supplier and its customer and in 1350℃, it is needed to use buried carbon or nitrogen protecting atmosphere B. Handle by special technical requirement | |||||||||||
| Item | Index | ||
| Allowable deviation size | Length, Width | ≤300 | ±1.0 |
| 301–500 | ±2.0 | ||
| ≥501 | ±0.5%（Max±4.0） | ||
| Thickness | ≤100 | ±1.0 | |
| ≥101 | ±1.5 | ||
| Distortion | Length≤300 | ≤ | 1.0 |
| Length＞300 | 1.5 | ||
| Crack Length | Width≤0.1 | no limit | |
| Width0.1–0.25 | ≤ | 50 | |
| Width＞0.25 | not allowed | ||
| Missing Angle length（a+b+c) | ≤ | 35 | |
| Missing Angle length（a+b+c) | 35 | ||
| Fusion hole | diameter | 5 | |
| Depth | 3 | ||