JP3196510B2 - Surface-coated tungsten carbide based cemented carbide end mill with excellent peel resistance with hard deposited layer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention is applicable to not only ordinary cutting but also heavy cutting such as high feed and high depth of cut with high heat generation without peeling of the hard vapor deposition layer. The present invention relates to a surface-coated tungsten carbide-based cemented carbide end mill that exhibits excellent cutting performance over a long period of time (hereinafter, referred to as a coated carbide end mill).

[0002]

2. Description of the Related Art Conventionally, as a coated carbide end mill, as shown in a plan view, an arrow A view, and a BB sectional view in FIG. The shank portion 1 and the cutting edge portion 2 are made of an alloy, and a plurality of outer cutting edges 3 are present in the cutting edge portion 2 at equal intervals while being twisted over the entire length. As shown in FIG. 3, the outer peripheral edge portion of the cutting edge portion is shown in a schematic partial cross-sectional view of the surface of the tip portion including at least the bottom edge 4 of the cutting edge portion 2 of the base S constituted by the rake face 3 b. It is known that the hard coating layer is coated with a hard deposited layer T of various compositions having a predetermined average layer thickness in a range of 0.5 to 15 μm formed by a chemical vapor deposition method and / or a physical vapor deposition method.

[0003]

On the other hand, in recent years, the performance of cutting machines has been remarkably improved, and in conjunction with the labor saving of the cutting work, there has been a tendency for cutting to be performed under cutting conditions in which the feed and the depth of cut are increased. In conventional coated carbide end mills, if this is used for high-feed cutting or high-incision cutting with the above-mentioned high heat generation, peeling is likely to occur in the hard deposited layer, and it is used in a relatively short time. At present, the life is reached.

[0004]

Means for Solving the Problems Accordingly, the present inventors have
From the above point of view, as a result of conducting research to develop a coated carbide end mill without occurrence of peeling on the hard vapor deposition layer,
The hard vapor deposition layer constituting the coated carbide end mill is formed by forming a lower layer of a Ti layer and a composite nitride of Ti and Al [hereinafter, (Ti, A
1) N)] is specified as a hard vapor deposition layer composed of an upper layer, and this is defined as one unit (hereinafter, this is referred to as a unit hard vapor deposition layer). As shown in the schematic partial cross-sectional view of FIG.
₁ and a portion of the cutting edge other than the formation of the single unit hard vapor deposition layer is formed by a plurality of unit hard vapor deposition layers T.
_The coated carbide end mill coated with ₁ , T ₂ , T ₃ and T ₄ can be used not only for ordinary cutting but also for cutting with high heat generation such as high feed cutting and high cutting depth. The research results show that the super-hard deposited layer exhibits excellent peel resistance and exhibits excellent cutting performance over a long period of time.

[0005] The present invention has been made based on the above research results, wherein the base comprising the cutting blade portion and the shank portion is made of a WC-based cemented carbide, and at least the tip of the cutting blade portion is formed. In a coated carbide end mill coated with a hard vapor deposition layer by a chemical vapor deposition method and / or a physical vapor deposition method, (a) a relief of a bottom blade at a tip end surface of the cutting edge portion and an outer peripheral edge also constituting the cutting edge portion (B) a portion of the cutting edge other than the formation of the single unit hard vapor deposition layer is covered with a plurality of unit hard vapor deposition layers; and (c) the unit hard vapor deposition layer. With the lower layer of the Ti layer,
The hard deposited layer, which is constituted by the upper layer of the (Ti, Al) N layer and satisfies the above requirements (a) to (c), is characterized by a coated carbide end mill having excellent peel resistance. Things.

The coated carbide end mill according to the present invention comprises: (a) a chemical vapor deposition method in which a flank of a bottom blade at a cutting edge portion of a base and at least a flank surface of an outer peripheral edge at a tip portion of the cutting edge portion are masked; And / or physical vapor deposition to cover with one or more unit hard vapor deposition layers, then remove the masking and cover at least the entire tip of the cutting edge with a single unit hard vapor deposition layer (B) Prepare the used coated carbide end mills used above, remove the hard deposited layer remaining on the flank of the bottom blade and the flank of the outer peripheral blade at the cutting edge portion of these used coated carbide end mills, and In a state where dimensions have been determined, it is desirable to manufacture at least the entire distal end portion of the cutting edge portion with a single unit hard vapor deposition layer, and the above (a) or (b) method. Good.

[0007]

Next, the coated carbide end mill of the present invention will be specifically described with reference to examples. As a WC-based cemented carbide substrate, a diameter having a composition corresponding to JIS standard M20: 1
A 0 mm general-purpose two-flute end mill (SED2100SG) was prepared.
(The unit hard-deposited layer is indicated by the symbol H in Table 1), and first, the bottom of the base at the cutting edge portion of the substrate. blade,
In addition, the flank of the outer peripheral blade is masked, and in this state, one or more of the unit hard vapor deposition layers as shown in Table 1 and FIG. 1 are formed on the surface of the substrate by an ion plating method classified as a physical vapor deposition method. (T _{2 to} T ₄ ),
Subsequently, the entire cutting edge portion was covered with the unit hard vapor deposition layer (T ₁ ) in a state where the masking was removed, thereby producing coated ultra-hard end mills 1 to 3 of the present invention. For the purpose of comparison, a conventional coated carbide end mill was manufactured under the same conditions except that the entire cutting edge portion of the substrate was coated with the single unit hard vapor deposition layer as also shown in Table 1.

[0008] Next, for the various coated carbide end mills obtained as a result, work material: S50C (carbon steel having a Brinell hardness: 236), cutting speed: 120 m / min, feed: 0.04 mm / tooth , Axial depth of cut: 15mm, Radial depth of cut: 1mm, Cutting time: 60 minutes, Welding high-feed high depth of cut cutting test by steel down-cut method, and measure the flank wear width of the cutting edge of the outer peripheral edge did. Table 1 shows the results of these measurements.

[0009]

[Table 1]

[0010]

From the results shown in Table 1, the coated carbide end mills 1 to 3 of the present invention have no peeling in the hard deposited layer despite high feed and high depth of cut accompanied by high heat generation. In contrast to the excellent abrasion resistance, it is apparent that the conventional coated carbide end mills have a hard deposited layer that peels off and reaches a service life in a relatively short time. As described above, the coated carbide end mill of the present invention peels off from the hard deposited layer even when used for not only ordinary cutting but also cutting with high heat generation such as high cutting depth and high feed cutting. Since it exhibits excellent cutting performance over a long period of time without occurrence of cutting, it has industrially useful characteristics such as high performance of cutting machines and sufficient satisfaction in labor saving of cutting work. .

[Brief description of the drawings]

FIG. 1 is a schematic partial cross-sectional view showing an outer peripheral edge of a coated carbide end mill of the present invention.

FIG. 2 is a front view of a base constituting the coated carbide end mill,
It is the arrow A view and BB sectional drawing.

FIG. 3 is a schematic partial cross-sectional view showing an outer peripheral edge of a conventional coated carbide end mill.

[Explanation of symbols]

S Substrate T Hard deposited layer T _{1 to} T ₄ Units Hard deposited layer 1 Shank portion 2 Cutting edge portion 3 Outer edge 3a Flank 3b Rake face 4 Bottom edge

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B23C 5/16 B23P 15/28 C04B 35/56 C23C 16/30 B23B 27/14

Claims (1)

(57) [Claims] 1. A substrate comprising a cutting edge portion and a shank portion is made of a tungsten carbide-based cemented carbide, and at least a tip portion of the cutting edge portion is covered with a hard vapor deposition layer formed by a chemical vapor deposition method and / or a physical vapor deposition method. In the end mill made of a surface-coated tungsten carbide-based cemented carbide, the bottom edge of the tip surface of the cutting edge portion, as well as the flank surface of the outer peripheral edge also constituting the cutting edge portion are coated with a single unit hard vapor deposition layer, A portion of the cutting edge other than the formation of the single unit hard vapor deposition layer is covered with a plurality of unit hard vapor deposition layers, and the unit hard vapor deposition layer is formed by a lower layer of a Ti layer, Ti and A
(1) An end mill made of a surface-coated tungsten carbide-based cemented carbide having a hard deposited layer having excellent peeling resistance, the end mill comprising an upper layer of a composite nitride layer of (1).