Medical designers have developed many different surgical saw blades, both motorless and alternating, oscillating and sagittal. Each of them is designed to provide accurate, precise and measurable cuts.
Traditionally, these blades are made of stainless steel, often type 304, classic type 18/8 and type 316 with the addition of molybdenum alloy to increase corrosion resistance. However, the selection of materials is increasingly critical due to industrial needs such as corrosion resistance, wear resistance and fatigue resistance.
Metal suppliers have developed new and proprietary chromium, nickel and molybdenum alloys to provide valuable combinations of properties that offer application-specific benefits.
Chromium provides the metal with its resistance to scratches and corrosion. Nickel ensures a smooth and polished finish. Molybdenum gives greater hardness and helps maintain a cutting edge.
Although there are many variations in alloy recipes, there are basically two main types of stainless steel: martensitic and austenitic. Surgical blades are made of martensitic steel because they are much harder than austenitic steel and are easier to keep sharp.
The blades were previously manufactured using traditional machining techniques, including 3- and 5-axis machining and laser cutting, but more recently non-traditional machining techniques have been used to fabricate these medical incision parts … i.e. photochemical and machining engraving. electric discharge wire (EDM wire).
Photochemical etching is a high precision controlled corrosion process with complex metal parts produced with very fine details.
The photo engraving process offers a more cost-effective alternative to drilling, drilling, laser and waterjet cutting when processing precision components made from thin-walled materials such as stainless steel, aluminum, and advanced “corrosion-resistant” technical alloys.
The use of photochemical engraving in the manufacture of saw blades has clear advantages. Shaping, including offset cube teeth and surface marking such as dividing lines, logos and identities, can be achieved economically in a single environmental process, thus avoiding possible heat and cold work deformation that can occur during CNC machining. The initial properties of the material remain unchanged throughout the engraving process and the parts are naturally burr free and do not require post-engraving processing.
With thicker materials or when parallel sidewalls are essential, wire EDM is the economical solution. The leaves can be stacked for the process. This is known for its high accuracy (± 5% of material thickness) and its ability to achieve a high level of surface quality.
As a new and innovative approach to the manufacture of medical saw blades, currently only a few chemical recorders can offer this combination of manufacturing ability and knowledge.
Chemical etching costs are the sum of various items, metal and photoresistance, labor (including engineering), technical cost, and machine time. General expenses, which consist of chemicals, water, electricity and waste treatment, as well as the usual service and administrative functions, should not be forgotten.
The cost of raw materials is likely to vary drastically in price. Of course, standard grades of stainless steel, nickel silver and brass will be considerably cheaper than exotic alloys such as beryllium, molybdenum, titanium and shape memory alloys.
Engraving consists of a combination of processes consisting primarily of glue and tools for sheet metal, cleaning, photoresist lamination, printing, development, photo-engraving and pickling.
Virtually every process has a working content, which makes it an essential element of the total cost. The workload is pretty much the same, regardless of the sheet size. For this reason, sheet size is a major factor in the cost of photo engraving.
Component prices are calculated per sheet, which means that smaller pieces or larger sheet sizes result in lower unit costs. However, the larger the sheet, the greater the dimensional tolerance across this sheet.