Tungsten Steel Waterjet Nozzle PM Sintered Parts

Product Introduction

Tungsten steel waterjet nozzle PM sintered parts are pressed and sintered tungsten-cobalt alloy. Due to its high hardness (HRA90), excellent wear resistance, and corrosion resistance, the nozzle has been widely used in sandblasting, shot peening, spray spraying, and other equipment, which ensures that the product can be used for a long time in the best air and abrasive. Advantages of tungsten carbide nozzles: Corrosion resistance, long service life, excellent performance, high-cost performance, and not easy to wear.

The invention belongs to the field of powder metallurgy, and relates to a superhard cemented carbide material and a preparation method thereof, more specifically, to a cemented carbide material for a water jet nozzle and a preparation method thereof.

Background Technique

In 1968, Dr. Norman Franz, a professor at the University of Michigan, invented high-pressure water jet cutting technology, also known as water jet cutting. In 1974, Flow Company of the United States successfully applied the pure water jet cutting system to industrial production. In the 1980s, the United States took the lead in advancing the water abrasive jet cutting technology to the practical stage, making the cutting objects more extensive. Among the many cutting methods, only high-pressure waterjet cutting belongs to cold cutting, which has many advantages: it can perform one-time cutting of any curve on the material, and the products after cutting do not need or are easy to be processed again, which is convenient, flexible and versatile. Extensive; do not use toxic, harmful gas or liquid, do not produce toxic substances or steam; slit does not produce heat-affected zone or mechanical deformation; can process materials that cannot be processed or are difficult to process by other processing methods, such as ceramics, composite materials, chemical fibers, heat-sensitive materials, etc.; safety, environmental protection, fast speed, and high efficiency. Taking laser cutting as an example for comparison, although the laser is superior to water jet cutting in terms of cutting speed in thin plate cutting, laser cutting costs are high in metal cutting above 16mm, and there is still a heat-affected zone around the kerf of laser cutting. The thickness of waterjet cutting metal materials can generally reach more than 30-100mm, and it has no effect on the material.

The working principle of the high-pressure water jet is to pressurize the liquid to 200-400mpa step by step with an ultra-high-pressure supercharger, and then pass through a nozzle with a diameter of less than 0.2mm to form a jet with a speed of up to 1000m/s and great kinetic energy. The water line forms a high-energy water jet, sprays on the surface of the workpiece, and destroys it. Adding abrasives such as quartz sand, alumina, corundum, and other abrasive jet cutting, the water jet has the characteristics of a saw blade, the cutting force is greatly improved, and almost any hard material can be cut.

Due to the harsh working requirements of the high-pressure water jet, the performance requirements for the material of the water jet nozzle are extremely high. The hardness of the commonly used high-pressure water jet nozzle material is required to be greater than 2700hv, and the material is required to have a very high relative density and no defects such as holes and cracks. , Good processing performance and impact resistance.

The addition of a binder phase to traditional cemented carbide will reduce the hardness and mechanical properties of cemented carbide. And in harsh environments, these bonds are more likely to be corroded and oxidized than the hard phase, which also reduces their wear resistance and corrosion resistance. WC (tungsten carbide)-based cemented carbide without binder phase refers to a WC cemented carbide material that does not contain or contains less than 0.5 wt% CO. Compared with traditional cemented carbide, wc-based cemented carbide without binder phase has more excellent wear resistance, corrosion resistance, excellent polishability, and other superior mechanical properties. However, tungsten carbide is a carbide with a high melting point (2870°C). In the absence of a binder phase, it is very difficult to obtain a dense cemented carbide without a binder phase using the traditional sintering method.

Existing studies have shown that by reducing the grain size of wc sintering powder, the sintering temperature can be reduced, and at the same time, the grain size can be refined, the hardness can be increased, and the mechanical properties can be improved; Large, adding hfc (hafnium carbide) as an inhibitor can effectively inhibit its grain growth; spark plasma sintering (spark plasma sintering, referred to as sps) has the advantages of rapid heating and cooling and lower sintering temperature, avoiding grain growth from the sintering process Great coarsening.

Metal Injection Molding Process

Detection Systems