JPS63278682A - Electron beam welding method - Google Patents

Abstract

PURPOSE:To prevent a welding crack by repeatedly projecting at high seed the beam widely oscillating in the energy density having the preheating or postheating action only and the beam narrowly oscillating capable of a penetration or the beam stopping the oscillation capable of penetration. CONSTITUTION:An abutted welding member 1 is welded in the direction of an arrow mark 2 and an electron beam 3 is oscillated at high speed in the X direction of an arrow mark 5 and Y direction of an arrow mark 6 by an electromagnetic deflecting coil 4 and projected on an electron beam pattern 7. The waveform 8 widely oscillating in the energy density having a preheating or postheating action and the waveform 9 narrowly oscillating in the energy density having the action capable of penetration are alternately repeated at high speed to execute welding with oscillating the beam in X and Y directions. In a 2nd method, the oscillation may be stopped temporarily in the section of the waveform 9 due to the action capable of penetration. The weld zone of high quality having no welding crack nor spatters is thus obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an electron beam welding method suitable for electron beam welding assembly of accelerator, rocket parts, etc.

[Conventional technology]

In electron beam welding assembly and construction of accelerator, rocket parts, etc., preheating and postheating are effective in preventing weld cracks in high carbon steel, etc., and in copper.

Preheating is extremely effective in welding aluminum alloys to obtain a smooth bead without spatter.

However, conventionally, there is no method to perform electron beam welding at the same time as preheating and postheating, and welding is performed after heating with an appropriate heat source in advance. Possible methods include using a heater such as a heater or preheating by electron beam irradiation, but it is difficult to heat and maintain members with large heat capacity, including jigs, to a predetermined temperature.

[Apex while the invention is trying to solve]

The present invention was proposed in view of these circumstances, and
The object of the present invention is to provide an electron beam welding method that can easily and accurately prevent weld cracking in high carbon steel, etc., and can produce a smooth spatter-free bead in copper, aluminum alloy, etc.

[Failure to solve intervening vertices]

To this end, the present invention provides beams that are broadly oscillated to an energy density that does not involve penetration and only has the effect of preheating or postheating, and beams that are oscillated narrowly to an energy density that has the effect of obtaining penetration. Alternatively, in order to achieve penetration, welding is performed by repeatedly irradiating a beam with the oscillation stopped at high speed alternately.

[For production]

With the above configuration, it is possible to obtain an electron beam welding method that can easily and accurately prevent welding cracks in high carbon steel, etc., and can produce smooth beads without spatter in copper, aluminum alloys, etc.

〔Example〕

An embodiment of the electron beam welding method of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing an embodiment of the method of the present invention;
Figure 2 is a current waveform diagram of the Dentake deflection coil according to the first method of the present invention, Figure 6 is a similar current waveform diagram of the second method, Figures 4 and 5.
The figures are plan views of the beam deflection patterns of FIGS. 2 and 3, respectively.

First, in FIG. 1, reference numeral 1 indicates welding members that are butted together and are welded in the direction of arrow 2. Reference numeral 3 denotes an electron beam, which is oscillated at high speed by an electromagnetic deflection coil 4 in the X direction of arrow 5 and the Y direction of arrow 6. 7 shows an oscillated electron beam pattern.

The first method of the present invention carried out according to the embodiment shown in FIG.
As shown in FIG. 2, the current waveforms 8 and 9 flowing through the electromagnetic deflection coil 4 cause the beam to oscillate in the X and Y directions.

That is, a waveform 8 for oscillating broadly to an energy density that only has the effect of preheating or postheating, and a waveform 9 that oscillating narrowly to an energy density that has the effect of obtaining penetration, at a frequency of several hundred Hz to around IKHz. Welding is performed by repeating alternately at high speed and oscillating the beam in the X and Y directions.

Further, in the second method of the present invention, as shown in FIG. 3, temporary oscillation occurs to obtain penetration. Welding is carried out with stops 10 being repeated at high speed alternating with waveforms 8 for widely oscillating energy densities that have only a preheating or postheating effect.

When performing beam oscillation as shown in Figures 2 and 3,
Beam deflection patterns 11 shown in FIGS. 4 and 5, respectively
, and the portions corresponding to the current waveforms 9 and 10 are shown as beam deflection patterns 12 and 13, respectively.

Thus, in the method of the present invention, electron beam welding can be performed simultaneously while performing preheating or postheating by alternately and repeatedly irradiating a beam that only has the effect of preheating or postheating and a beam that has the effect of obtaining penetration at high speed. It is possible to obtain the desired high-quality welds without weld cracks or spatter.

〔Effect of the invention〕

In short, according to the present invention, a beam is widely oscillated at an energy density that does not involve penetration and has only the effect of preheating or postheating, and a beam is oscillated narrowly at an energy density that has the effect of obtaining penetration.・By alternately and repeatedly irradiating a beam with oscillation or a beam with oscillation stopped to obtain penetration at high speed, weld cracking of high carbon steel etc. can be easily and accurately prevented. Can also be made of copper,
The present invention is extremely useful in the nitriding industry because it provides an electron beam welding method that can produce a smooth weld without spatter on aluminum alloys and the like.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an embodiment of the electron beam welding method of the present invention, FIG. 2 is a current waveform diagram of the electromagnetic deflection coil according to the first method of the present invention, and FIG. 3 is a similar current waveform diagram of the second method. 4 and 5 are plan views of the beam deflection patterns of FIGS. 2 and 3, respectively. DESCRIPTION OF SYMBOLS 1... Welding member, 2... Welding direction, 6... Electron beam, 4... Electromagnetic deflection coil, 5, 6... Oscillation direction, 7... Electron beam pattern, 8, 9... Electromagnetic deflection coil current waveform, 10... Oscillation stop, 1
1j12, 13... Beam deflection pattern. Agent Masa Tsukamoto, Patent Attorney Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] A beam oscillated to a wide energy density that does not involve penetration and only has the effect of preheating or postheating, and a beam oscillated narrowly to an energy density that has the effect of obtaining penetration. Or an electron beam welding method characterized by welding by alternately and repeatedly irradiating the beam with a beam whose oscillation is stopped in order to obtain penetration at high speed.