China Ultra Fine Grain Tungsten Carbide Rod Blanks For PCB Micro Drill Bit Manufacturing Manufacturers, Supplier
Product Description
| Grade | Co (%) | Grain Size (μm) | Density (g/cm³) | Hardness | Application |
|---|---|---|---|---|---|
| KT308H | 8 | 0.3 | 14.55 | 2060 | Suitable for high-speed copper clad laminate (CCL) |
| KT305H | 5 | 0.5 | 14.92 | 2180 | Suitable for IC substrate machining |
| KT209 | 9 | 0.2 | 14.45 | 1960 | Suitable for general machining of various PCB boards |
Main sizes of drill blank rods: Φ1.0-330, Φ1.15-330, Φ1.3-330, Φ1.5-330, Φ2.0-330, Φ2.5-330
Note: Φ1.0-330 is the most widely used grade.
Product Description
This carbide rod blank is specially developed for high-end PCB drill bits. Supported by refined production equipment, mature processes, strict environmental control and premium raw materials, it features guaranteed precision, stability and purity, ideal for manufacturing high-precision micro drills and IC substrate drills.
Made via dedicated extrusion forming and 10MPa uniform-pressure sintering, the blank avoids uneven density and irregular microstructure. Consistent density and homogeneous grain structure across batches enable finished drill bits with high drilling accuracy, outstanding wear resistance and low breakage risk.
Produced in clean workshops with closed-loop temperature & humidity control, the material stays free from dust and impurities for reliable surface cleanliness and consistent quality. It is manufactured independently without mixing other carbide grades, eliminating cross-contamination and meeting strict purity requirements of micro drills and IC substrate drills.
It adopts high-purity WC powder from top-grade sources. With professional powder mixing and custom formula, the blend is uniform and stable to deliver high strength and toughness. Japan-sourced oil-based wax extrusion ensures even binder removal, preventing carbon residue and internal defects that cause drill bit performance loss and short service life.
Every production step, from high-purity raw material batching, precise mixing, extrusion forming, constant-temperature & constant-pressure sintering to clean handling, is finely controlled. These premium carbide rod blanks serve as dependable base stock for high-end PCB drills, ultra-micro drills and high aspect ratio precision drills.
KT308 Drill Bit Material Overview
1. Chemical Component (Wt%)
| Grade | WC | Co |
|---|---|---|
| KT308 | 91.8-92.8 | 7.2-8.2 |
2. Physical Properties
| Hardness (HV30) | Density (g/cm³) | TRS (N/mm²) | Grain Size (μm) | Porosity |
|---|---|---|---|---|
| 1960-2060 | 14.45-14.65 | ≥4500 | 0.3 | A02 B00 C00 |
3. Microstructure
4. Application
KT308 Grade is special used for PCB drill bits, recommended for cutting diameters ≤0.3 mm, High length-to-diameter ratio.
Frequently Asked Questions (FAQ)
KT308H is specifically designed for high-speed copper clad laminate (CCL), KT305H is tailored for IC substrate machining, and KT209 is suitable for general machining of various PCB boards.
While sizes range from Φ1.0-330 up to Φ2.5-330, the Φ1.0-330 size is the most widely adopted specification.
10MPa uniform-pressure sintering prevents uneven density and irregular microstructure, resulting in homogeneous grain distribution, higher drilling accuracy, enhanced wear resistance, and reduced risk of tool breakage.
KT308 features a hardness of 1960–2060 HV30, a density of 14.45–14.65 g/cm³, transverse rupture strength (TRS) ≥4500 N/mm², a fine grain size of 0.3 μm, and A02 B00 C00 porosity.
It guarantees uniform binder removal during processing, eliminating carbon residue and internal microstructure defects that could otherwise degrade drill bit performance and shorten tool lifespan.
KT308 is specifically recommended for micro PCB drill bits with cutting diameters ≤0.3 mm and applications requiring a high length-to-diameter ratio.
