What are the advantages of using sandblasting machine for surface treatment of metal medical devices?

The surface treatment of metal medical devices by sand blasting machine can solve the strict requirements of surface cleanliness, biocompatibility, structural accuracy and durability, and the specific advantages can be developed from the following core dimensions:

First, efficiently remove surface pollutants and meet medical-grade cleanliness standards.

During the processing of metal medical devices (such as surgical instruments, implants, diagnostic equipment parts), pollutants such as oil stain, scale, heat treatment residue, cutting fluid, etc. are easy to remain on the surface, which will directly affect the adhesion and biocompatibility of subsequent coatings, and even lead to the risk of postoperative infection.

Sandblasting machine can clean the surface without dead angle by spraying abrasive (such as quartz sand, alumina, glass beads, etc.) at high pressure;

It can completely remove micron-scale oil stains and oxide layers, and avoid chemical pollution that may remain after chemical cleaning;

The cleaning effect on complex structures (such as tooth grooves, holes and joints of instruments) is better than manual wiping or pickling, so as to ensure that the surface cleanliness meets the requirement of "no impurity residue on parts in contact with human body" in the Quality Management Standard for Medical Device Production.

Second, improve the controllability of surface roughness and optimize biocompatibility and functional adaptation.

The surface roughness of medical metal parts (such as orthopedic implants and dental implants) directly affects the ability of cell adhesion and tissue integration; The surface roughness of surgical instruments (such as hemostatic forceps and tweezers) is related to the grip stability and anti-skid performance.

Sandblasting machine can accuRately control the surface roughness (ra value) by adjusting the abrasive type, particle size and injection pressure;

For implants, a "micro-rough surface" (Ra 1.5-3.0μm) is made by using fine-grained abrasive (such as 0.1-0.3mm glass beads), which can not only promote the attachment and growth of bone cells, but also avoid tissue irritation caused by excessive roughness;

For surgical instruments: through the treatment of medium-coarse abrasive (such as 0.5-1.0mm alumina), the surface will form a uniform matte texture, improve the grip friction, and avoid the reflection from affecting the surgical field of vision.

Third, strengthen the surface mechanical properties and prolong the service life of the instrument.

Metal medical devices are subject to repeated disinfection (high temperature and high pressure, chemical sterilization), frequent use of friction and impact, and the surface is prone to scratches, corrosion or fatigue damage.

The "shot peening strengthening" function of sandblasting machine can optimize the surface mechanical properties;

Formation of surface compressive stress layer: When the abrasive hits the metal surface at high speed, the surface metal will be plastically deformed, and a compressive stress layer with a depth of about 50-100μm will be formed, which will offset the tensile stress generated in the use of instruments and reduce the probability of fatigue cracks (for example, the service life of orthopedic steel plates can be increased by more than 30%);

Improve corrosion resistance: there is no oxide layer and impurity residue on the cleaned surface, which can reduce the "corrosion source" of electrochemical corrosion; If it is followed by passivation treatment, the rough surface pretreated by sandblasting machine can also enhance the adhesion of passivation film and further improve the corrosion resistance of stainless steel, titanium alloy and other materials (especially suitable for repeatedly disinfected instruments).

Four, non-contact processing, to ensure the accuracy and integrity of the instrument structure.

Metal medical instruments (such as precision biopsy needles and catheter joints of minimally invasive instruments) are mostly thin-walled, irregular or high-precision structures. Traditional mechanical grinding is easy to lead to dimensional deviation and edge deformation, while chemical pickling may corrode the metal matrix.

The non-contact processing characteristics of sandblasting machine can avoid this problem:

Abrasive spraying only acts on the surface, and will not damage the geometric dimensions of the instrument (such as aperture, wall thickness and tolerance), especially suitable for processing precision parts with tolerance requirements of ±0.01mm;

For sharp blades (such as scalpels and scissors blades), flexible abrasives (such as resin sand) can be selected to avoid edge curling or passivation while cleaning the surface, so as to ensure the use function of the instrument.

Fifth, adapt to the compliance of the medical industry and reduce the risk of pollution.

The production of medical products must meet strict environmental protection and safety standards, and the advantages of sandblasting machine in this dimension are obvious:

Environmental protection: some sandblasting machines are equipped with "abrasive recovery system", which can realize abrasive recycling (for example, the recovery rate of glass beads is over 95%) and reduce solid waste discharge; If dry sand blasting and high-efficiency dust removal device are adopted, the waste water pollution caused by wet sand blasting can be avoided, which meets the requirements of "zero pollution discharge" in medical industry;

Compatibility of materials: Special abrasives can be selected according to the metal materials of medical devices (stainless steel, titanium alloy, cobalt-chromium alloy, etc.) (for example, chlorine-containing abrasives are prohibited for titanium alloy parts to avoid stress corrosion), so as to ensure that no harmful substances are precipitated from the treated materials, which meets the requirements of "no cytotoxicity and no sensitization" in Biological Evaluation of Medical Devices (GB/T 16886).

summary

The core value of the surface treatment of metal medical devices by sandblasting machine lies in the synergistic satisfaction of * * "cleanliness, precision, performance and compliance"-it not only solves the core requirements of medical products for surface cleanliness and biocompatibility, but also improves the functional adaptability and durability of the devices through controllable roughness adjustment and mechanical strengthening, while avoiding the risk of precision damage and pollution in traditional treatment methods, which is one of the core technologies of surface treatment of medical metal parts.