JPH03251304A - Microdrill made of trisilicon tetranitride sintered body - Google Patents

Abstract

PURPOSE:To increase a wear resistance, by sintering and forming the mixed powder which contains more than one kind at least of MgO, Y2O3, Al2O3, AlN, ZrO2, HfO2, TiC and TiN at 0.01 - 20 wt% and the balance of Si3N4. CONSTITUTION:A microdrill made of Si N sintered body is manufactured by sintering and forming with the use of the mixed powder containing more than one kind at least of MgO, Y2O3, Al2O3, AlN, ZrO2, HfO2, TiC and Ti Nat 0.01 - 20 wt% on the respective components and the balance of Si3N4. Since the Si3N4 has the hardness about equal to those of the carbide and carbo-nitride of Ti and is excellent in the deposition resistance in the case of performing the punching of a printed board, an extremely good wear resistance and deposition resistance are shown and the tool life is elongated as well.

Description

[Detailed Description of the Invention] <Industrial Application Field> This invention exhibits excellent wear resistance, especially when used for drilling holes in printed circuit boards, and can be used for drilling holes with excellent dimensional accuracy over a long period of time. This invention relates to a micro drill made of Si3N4 sintered body that can perform the following.

<Conventional technology> Conventionally, micro drills made of WC-based cemented carbide without a hard layer on the surface, physical vapor deposition methods such as ordinary chemical vapor deposition method, ion blasting method, and sputtering method have been used. using carbides such as Ti or Zr,
A surface-coated WC-based alloy microdrill with a hard surface layer of 082 to 2011 m in thickness, consisting of one or more than two types of nitrides and carbonitrides, can be used for printing on printed circuit boards, etc. It is well known that it is used to form holes of about 0.5 to 1 mm.

<Problem to be solved by the invention> However, in recent years, when drilling holes in these printed circuit boards,
Labor saving and speeding up became necessary, and the drilling conditions became more severe. For this reason, in conventional WCC cemented carbide microdrills and surface-coated WC-based alloy microdrills, the hard surface layer may wear out or peel off in a short period of time, or the workpiece may adhere to it. Currently, it does not exhibit the required wear resistance.

<Means for Solving the Problems> In view of the above, the present inventors have developed a method with excellent wear resistance,
As a result of researching and developing microdrill materials that are resistant to welding, MgO, Y2O3, AJ! 20! , AJ!
At least one of N, Zr0a, Hf0z, TiC, and TiN at a concentration of 0.01 for each component.
When a micro drill made of a 313N4 sintered body is produced by sintering and molding a mixed powder containing ~20% by weight and the remainder is 5taN4, it exhibits extremely good wear resistance and welding resistance, It has been found that the tool life is also extended.

<Function> That is, the present invention is characterized by a micro drill made of a 5LN4 sintered body obtained by sintering and molding the above-mentioned mixed powder. This is because it has almost the same hardness as carbonitrides and carbonitrides, and has excellent adhesion resistance when drilling holes in printed circuit boards.

<Example> Next, the microdrill of the present invention will be described with reference to an example.

First, the outer diameter of the cutting edge: 0.8 mm, the blade length: 30. Om
A microdrill made of Si3N4 sintered body of the present invention having a shape of JTS B 4301 with dimensions of m was manufactured. Also, for comparison, 1. A well-known vacuum was applied to the surface of a WCC cemented carbide microdrill having a composition equivalent to JIS-KIO (hereinafter referred to as comparative drill l) and a WCC cemented carbide microdrill having a composition equivalent to JIS-KIO. 2. Ti nitride was deposited using an arc evaporation method. A surface-coated WC-based cemented carbide micro drill (hereinafter referred to as Comparative Drill 2) having a layer thickness of nlIm was manufactured.

For these various micro drills, the workpiece material: three four-layer sheet plates sandwiched between a 0.12 mm thick aluminum plate and a 1.6 mm thick base and clite plate with a total thickness of 6 mm.
．． Drilling was performed on a 55 mm Benont board under the following conditions: Rotation speed: 60.00 Or, p, m Cutting speed: 40011 mm/min Feed rate: 50++ m/rev Until the hole inner diameter surface roughness reached 301+ m, which is the criterion for determining service life. The number of holes drilled was measured, the cutting edge was observed, and the welding state of the work material was examined. The results of these measurements are shown in Table 1.

Table 1 <Effects of the Invention> From the results in Table 1, the micro drill made of Si3N4 sintered body of the present invention exhibits superior wear resistance and welding resistance compared to the conventional comparative drill 1.2. is clear.

In this way, the micro drill made of Si3N4 sintered body of the present invention can be used for drilling holes in printed circuit boards.
ial'J4 has excellent wear resistance and welding resistance, so it can be used even when drilling under harsh conditions.
This allows drilling with good dimensional accuracy over a long period of time.

Claims (1)

[Claims] MgO, Y_2O_3, Al_2O_3, AlN, Z
Contains 0.01 to 20% by weight of at least one of rO_2, HfO_2, TiC, and TiN, and the remainder is Si_
A micro drill made of a Si_3N_4 sintered body made by sintering and molding a mixed powder of 3N_4.