JPS6169919A - Wire for dot printer - Google Patents

Abstract

PURPOSE:To obtain a wire for dot printer superior in toughness and wear resistance, by solution treating the drawn wire coil of a steel consisting of a specified compsn., then drawing said coil to wire and age treating it under specified conditions. CONSTITUTION:The drawn wire coil of the steel composed of, by weight 0.04-0.20% C, <=0.10% Si, <=0.10% Mn, 16.0-19.0% Ni, 3.0-6.0% Mo, 7.0-13.0% Co, 0.05-0.20% Al, 0.50-1.90% Ti and the balance Fe with impurities is solution treated by water at about 820 deg.C to obtain hardness about 30-35HRC. Next, said coil is wire drawn at >=70% area reduction ratio to wire having a prescribed size of about 0.3mm diameter, then said wire is age treated at about 480 deg.C to precipitation harden it to >=700Hv.

Description

[Detailed description of the invention] Wire drawing process to make ultra-fine wire is very easy.
The present invention also relates to a wire for dot printers that can be easily heat treated and has excellent toughness and wear resistance.

A dot printer operates multiple wires to
It prints predetermined characters or numbers, and its printing speed is extremely fast. Printed wires are required to have high abrasion resistance, toughness, high fatigue strength, easy wire drawing and heat treatment, and good corrosion resistance.

Currently, ultrafine wires quenched at high speed fI4 are commonly used for printed wires. High speed steel wire.

is manufactured by repeatedly drawing and drawing wire into ultra-fine wire, quenching and tempering it, and then cutting it. However, it is expensive because it requires a long wire-drawing process to make the wire into an ultra-fine high-speed steel wire. It has the disadvantage of being expensive. Also, although it has excellent wear resistance, it lacks toughness and may break during use.

The present invention has been made in view of these problems.
The purpose of the present invention is to provide a wire for a dot printer which is extremely easy to draw into an ultra-fine wire, easy to heat cure, and has excellent toughness and abrasion resistance.

That is, the present invention provides Cθθg~a2θchi, Stθ/θchi or less, Mnθ/θchi or less, Ni/&θ~15! θchi, Mo
! θ～&θchi, Co 7θ～/3θchi, AJ 120
j ~ θ2θ, TiO3; 0 ~ /2θ Chi A rolled steel coil consisting of the remainder iron and impurities is heated to about 20°C and water-cooled for solution treatment, and then wire drawn to an area reduction of 7θ Chi. Then, the diameter is made thinner by repeating the process of solution treatment, followed by IW drawing with an area reduction of about 2θ, and finally wire drawing with an area reduction of about 2θ. θ3
Wires with predetermined dimensions before and after the group, and then t, t
This is a wire for dot printers which is characterized by being precipitated hardened to Hv7θθ or higher by aging treatment for around 3 hours at around lro°C, and has excellent performance in both toughness and wear resistance.

Next, the reasons for limiting the composition of the wire for dot printers of the present invention will be described. C combines with Ti to form a hard special carbide T
ide is formed and is effective in improving wear resistance, but θθ4t
% ungrooved, the effect is small, and if C exceeds a2θcst-, the toughness is impaired, so it was set to θθda to θλθ. Si
Although Mn and Mn have a deoxidizing effect, if the content exceeds a/θ, the toughness decreases, so they were each set at a/% or less. Ni
is necessary to form a martensitic structure, and is also necessary to stabilize martensite up to the temporary working temperature of 1, but if it is less than /6 inch, the effect is not small, and if it exceeds /2 inch, residual austenite will be formed. Because it hails/mu θ~/
9. I set it to θ. Mo is necessary to create an intermetallic compound and cause precipitation hardening through aging treatment, but if it is less than 3%, the effect is not small, and if it exceeds 6%, the toughness decreases, so it was set as 3θ to much θ. O.

Although gold has the effect of accelerating precipitation hardening due to Mo, 7
If it is less than 73%, the effect is small, and even if it exceeds 73%, the effect is small, so it was set as 7θ to /3θ. Aλ is added as a deoxidizer and also improves age hardening properties, so θθ
j~θλθchi.

Ti forms the intermetallic compound Ni3Ti, which is necessary to cause precipitation hardening, and also combines with carbon to form a special carbide that improves wear resistance, but if it is less than 650%, the effect is small and l? If it exceeds est-, the toughness decreases, so θj-/? %.

Steel of this composition is approx. By solution treatment at r2θ℃ water cooling, it becomes low carbon martensite with special carbide TiO dispersed in it.The hardness is relatively soft with HROJθ~35, so it is easy to draw wire, and there is no intermediate solution treatment. Cold drawing wire drawing with an area reduction rate of about 2j%-j is possible. In this way, after performing cold wire drawing with a strong resistance with an area reduction rate of 7θ or more, when aging treatment is performed for 4tgθ℃X Jh (hours), H
It can be precipitation hardened to a high hardness of v7θθ to 7Sθ.

That is, steel with this composition has Hv7θθ~7j due to precipitation hardening.
Since it has a structure in which hard special carbide Ti0 particles are dispersed in the low carbon martensite matrix which has become θ, it is possible to have both toughness and wear resistance t-.

Next, the effects of the present invention will be explained using examples.

Table 1 shows the chemical composition of the wire of the present invention and the wire made of 8KH5'.

Table 1 Printer wire chemical composition Symbol A indicates a wire having the composition according to the present invention, symbol B indicates SKH?
indicates the year. The SKH wire with symbol B can be drawn by cold drawing without intermediate annealing at an area reduction rate of 3θ to 0.03, so it is necessary to draw the SKH wire by cold drawing from 3θ to 0.030°. Annealing is performed 72 to 6 times. On the other hand, steel with the symbol can be drawn without intermediate solution treatment up to an area reduction of approximately 2θ%, so the intermediate solution treatment required to draw from a 5J simple φ coil to a θ3φ wire is , only 3
It's time. In this way, it is very easy to draw the wire into a wire.

Table 2 Durability Test Results Table 2 shows the heat treatment hardness of the OJ tymφ wire and the breakage rate after conducting a hammering test 796 times as a pre/twisted wire. In other words, symbol A indicates that the wire drawing coil is subjected to solution treatment at λθ°C, cold drawing with an area reduction of 29 to φ0.3, and then subjected to aging treatment for a length of θCXJh (hours). , Hv73θ. As a result of the hammering test of the printer wire with the symbol B 796 times, the breakage rate of the symbol B was /yo%, while the breakage rate of the symbol B was 0%, and the wire of the present invention was 0% strong. It turns out that he has excellent sex. In addition, the wear resistance of symbol A is almost as good as symbol B.

As explained above, (1) the present invention provides Ca0 da to θyu θchi, s
Below iθ/θ, Mn O, below /θ, Ni/&θ~
15! θ Chi, Mod θ-40% * Co “θ~/3
θchi, A1905~620%%Ti0jθ~/, 90
A wire drawing coil made of steel with no remaining iron or impurities is subjected to a wire drawing process with an area reduction rate of about 0 inches after solution treatment, and drawn into a wire of a predetermined size with a diameter of about θ3, and then , 0 to 0
This wire for dot printers is characterized by being precipitated and hardened to Hv7θθ or higher by aging treatment at around 100°C, and has excellent performance in terms of strength, toughness, and abrasion resistance.

Patent applicant: Plus Engineering Co., Ltd. Representative patent attorney: Izawa Jiku.

Claims (1)

[Claims] In weight%, C 0.04 to 0.20%, Si 0.10% or less, Mn 0.10% or less, Ni 16.0 to 19.0%,
Mo3.0-6.0%, Co7.0-13.0%, Al
A drawn steel wire coil consisting of 0.05 to 0.20% Ti, 0.50 to 1.90% Ti, and the balance iron and impurities is subjected to a wire drawing process with an area reduction rate of 70% or more after solution treatment to obtain a wire with a diameter of 0. .3m
The wire is drawn to a predetermined size of around 48 m, and then 48 m
A wire for dot printers with excellent toughness and wear resistance, characterized by being subjected to aging treatment at around 0°C and precipitation hardened to Hv700 or higher.