JPS62102970A - Hard sn lapping surface plate - Google Patents

Abstract

PURPOSE:To maintain and improve abrasion resistance and flatness by constituting a lapping surface plate of 93-95wt% of Sn and the rest of Pb, with less than 5wt% of at least a metal of Cu, Al and Zn added thereto. CONSTITUTION:When a lapping machine is operated, a disc 1 and a lapping surface plate 2 are rotated by a drive 3 to cause a dressing ring 7 supported by an arm 6 to be rotated on its axis. Also, a workpiece 4 adhered to a lapping ring 5 is rotated on its axis to be polished by free abrasive grains 8. In this case, the lapping surface plate 2 is constituted of 93-95wt% of Sn and the rest of Pb, with less than 5wt% of at least a metal of Cu, Al and Zn added thereto. This lapping surface plate 2 has such a good abrasion resistance, that the manhour for exchanging and recessing can be reduced by half, and it has such a good flatness, that the workpiece can be finished with high accuracy.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to improvement of a lapping surface plate, particularly to maintenance and improvement of Sn surface plate wear and maintenance and improvement of Sn surface plate flatness.

[Conventional technology]

A typical lapping machine has a structure as shown in FIG. 1, for example. The disk l3 supported by the main shaft and the lapping surface plate 2 mounted on it drive the main shaft! ! It rotates by position 3. This rotational movement causes the correction ring 7 supported by the arm 6 having a roller guide to rotate. In addition, the workpiece 4 glued to the ranofring 5 also
Rotates within the correction ring. Workpiece 4 is ground with a free-11 whetstone 8.8 on a rasobing surface plate.

The material of the conventional lapping surface plate is Sn, which is 90% by weight.
The remainder had a composition consisting essentially of Pb ◇ [Problem to be solved by the invention] Since the Sn lapping surface plate described above is soft, the surface plate is corrected by the correction ring so that constant a wear is accelerated. , for example, Binochi 0.4
m groove depth Q. l mx, using a trapezoidal groove on a surface plate with a groove trough angle of 120'', Mn-Zn ferrite as the workpiece, and 1μ of diamond as the free abrasive grain (when machining is performed using sheep crystalline particles, O in 30 hours in groove depth direction
．． OBtnxo) It has worn out. In addition, the surface plate may be partially uneven, and the flatness of the surface plate should be adjusted to 7 to 10.
The object of the present invention is to promote the wear resistance of the lap surface plate when it is difficult to maintain the temperature below μm/100m.

[Means for solving the problem] In the present invention, in order to achieve the above object, the weight % of Sn is set to 93 to 95. In the present invention, it is also possible to use a Sn wrapping surface plate in which 5% by weight or less of at least 13 types of metals such as Cu, A2, and Zn are added to the Sn wrapping surface plate material. Regarding the tarp hardness of Sn and PB, the amount of Sn is greater than the amount of PB, so increasing the weight% of Sn increases the hardness of the surface plate, but considering the surface accuracy of the workpiece, it is necessary to increase the hardness of Sn by 95% by weight. If it exceeds %, the hardness will increase too much and chipping will occur on the edge of the workpiece, so this is the limit. In addition, the four types of metal materials other than Sn and Pb have higher hardness than Sn, and we selected materials that do not have a negative effect on the characteristics of the workpiece in the post-processing process. Therefore, by changing the amount of Sn from 90 to 97% by weight and using a surface plate made of a 5n-Pb alloy with Sn at 93% by weight and the rest being Pb, the workpiece was placed in a modified 11 ring of silk with a diameter of 110 mm! A bonded wrap ring with a diameter of 1001 m was inserted, and the plate was mounted on a lapping machine rotating at 5 Qrpm, and lapped with free diamond abrasive grains of 1 to 5 μm. When lamped for 30 hours under the conditions, the groove of the lap becomes 0.08 mm in the groove depth direction, and the flatness of the surface plate becomes 7 to 10 μm/100 plates, but in the case of the lap surface plate of lV & 12 and 3 according to the present invention, , 60
After time lapping, wear was suppressed to 0.08 mtn in the n depth direction, and the flatness of the surface plate was maintained at 5 μm/loo or less. When a material with a bulk of 4, in which 5njl was larger than that of the present invention, was used, the workpiece was chipped, cracked, etc. during processing.

Although not shown here, the material of the wrapping surface plate is S.
In addition to Sn and Pb, good results were also obtained with separated metal materials of Cu, Aj, and Zn. Because the wear resistance of S is excellent with a wear rate of 0.08 in 60 hours in the depth direction,
The man-hours for replacing the lap surface plate and the man-hours for groove machining can be halved. In addition, since the flatness of the surface plate is only 5 μm/100 mm, the dimensions of the workpiece can be finished with perfect precision.

[Brief explanation of drawings]

FIG. 1 shows a plan view 1 and a sectional view of a conventional lapping machine. 1: Disc, 2: Wrapping surface plate, 3: Drive device. 4: Workpiece, 5 Niratsubling, 6: Arm.

Claims (1)

[Scope of Claims] 1. A hard Sn lapping surface plate characterized by having a composition of 93 to 95% by weight of Sn and the remainder substantially consisting of Pb. 2. The hard Sn wrapping surface plate according to claim 1, further containing 5% by weight or less of at least one metal of Cu, Al, and Zn.