Vacuum brazing is a high-performance bonding process for diamond blades, forming metallurgical bonding between diamond grits, brazing alloy, and steel matrix in a high-vacuum, oxygen-free environment. It features high bonding strength, high diamond exposure, and excellent cutting performance. Below is the complete industrial production process:

1. Raw Material Preparation
Core Materials
Steel Matrix: High-strength alloy steel (65Mn, 45# steel, 75Cr1) – circular saw blank, laser-cut or stamped to shape.
Diamond Grits: Synthetic industrial diamond (sorted by mesh size, strength, and thermal stability).
Brazing Alloy: Active brazing filler (mainly Ni–Cr–B–Si, Cu–Sn–Ti, Ag–Cu–Ti) – contains active elements (Ti, Cr, Zr) to wet diamond surfaces.
Auxiliaries: Flux (rarely used in high vacuum), cleaning agents, anti-oxidation protectants.

2. Steel Matrix Pre-Treatment
Purpose: Remove oil, rust, oxide scale to improve brazing adhesion.
Alkaline Degreasing: Hot alkaline solution cleaning.
Acid Pickling / Sandblasting: Remove oxide layer and surface contaminants.
Drying & Preheating: Low-temperature drying to eliminate moisture.
Mechanical Shaping: Grinding, flattening, and trimming the matrix to dimensional tolerance.

3. Diamond Selection & Surface Modification
Screening & Classification: Sort diamond by particle size, purity, and impact resistance.
Diamond Surface Metallization (Optional but critical): Coating diamond with Ti, Cr, W, or Mo via physical/chemical deposition to improve wettability with brazing alloy.
Uniform Distribution: Manual or automated arrangement of diamond grits on the matrix working surface.

4. Brazing Alloy Preparation & Placement
Brazing Alloy Form: Amorphous foil, paste, powder, or wire.
Precise Placement:
Apply brazing alloy evenly between diamond and matrix.
Use fixtures or jigs to fix diamond position and prevent shifting during heating.

5. Assembly & Vacuum Furnace Loading
Tool Fixturing: Use graphite or ceramic fixtures to fix matrix and diamond layers.
Furnace Loading: Place assembled blanks evenly in the vacuum brazing furnace.
Sealing & Evacuation:
Close furnace chamber; start vacuum pumping system.
Vacuum Level: Generally controlled at 10⁻³ ~ 10⁻⁵ Pa (high vacuum to avoid oxidation).

6. Vacuum Brazing (Core Process)
Program-controlled temperature & vacuum curve:
Low-Temperature Preheating (200–450°C): Remove residual moisture and volatile impurities.
Medium-Temperature Heating (450–Braze Temperature): Slow heating to reduce thermal stress.
Brazing Holding Stage:
Typical temperature: 680–950°C (depends on brazing alloy type).
Holding time: 5–20 minutes (ensure full melting, spreading, and reactive bonding).
Maintain high vacuum throughout to prevent diamond graphitization and matrix oxidation.
Key reaction: Active elements (Ti/Cr) in brazing alloy react with diamond surface to form carbides (TiC, Cr₇C₃), realizing strong metallurgical bonding.

7. Controlled Cooling in Furnace
Furnace Cooling / Nitrogen Quench Cooling:
Slow cooling to avoid matrix deformation and cracking.
Cool to below 200°C before venting and opening the furnace.
Prevent rapid oxidation during cooling.

8. Post-Processing & Finishing
Deburring & Trimming: Remove excess brazing alloy flash.
Dynamic Balancing: Correct unbalance for high-speed rotation.
Surface Grinding / Sharpening: Optimize diamond exposure and cutting edge.
Hole Machining & Slotting: Process mounting holes, expansion slots, chip grooves.
Anti-Corrosion Treatment: Anti-rust oil coating or surface passivation.

9. Quality Inspection & Performance Testing
Dimensional Inspection: Outer diameter, inner hole, thickness, runout tolerance.
Bonding Strength Test: Check for diamond drop-off via impact, shear, or cutting test.
Hardness & Microstructure: Verify brazing layer density and interface bonding.
Cutting Performance Test: Dry/wet cutting test for efficiency, lifespan, and edge stability.
Visual & Non-Destructive Test: Check for cracks, oxidation, or incomplete brazing.

10. Packaging & Warehousing
Clean, anti-rust packaging.
Label specification, diamond grade, application scope (stone, concrete, asphalt, ceramic, etc.).
Store in dry, low-humidity environment.
Key Advantages of Vacuum Brazed Diamond Blades
High bonding strength (diamond not easy to fall off).
High diamond exposure (up to 70–80%), high chip removal efficiency.
Suitable for high-speed, heavy-duty cutting (reinforced concrete, hard stone, etc.).
Uniform heating, small matrix deformation, high precision.

11.Konaflex has  5 types of brazed diamond products and their features and applications:                                           

 Metal+: Metal slices - stainless steel, carbon steel, cast iron, copper, aluminum profile and other metal materials. https://www.konaflextools.com/products_classification/94.html                        

Universal: Multi-Purpose Slicing — Stone, Concrete, Asphalt, Ceramic, Stainless Steel, Copper, Aluminum Profile, Cast Iron, Carbon Steel, Wood, Plastic.https://www.konaflextools.com/products/48.html                                                                                                                                                       

GranitePlus:  Granite Cutting Disc – This product can be used for cutting/grinding and is designed for fast, efficient cutting/sanding of high-hardness granite. https://www.konaflextools.com/products_list/240.html                                                                                                                                                                         

RockSlab: Slate Sheets — This product is used for cutting high hardness slabs/artificial stone, as well as sanding and trimming the burrs after cutting. https://www.konaflextools.com/products_list/241.html                                                                                                                                                                                               

GlassCut: Glass Slicing — This product is designed for cutting a wide range of glass products, as well as sanding and trimming edge burrs after cut. https://www.konaflextools.com/products_list/242.htm