CN104801805B - High-temp soldering method between multi-disc hard alloy and strip stainless steel knife rest - Google Patents
High-temp soldering method between multi-disc hard alloy and strip stainless steel knife rest Download PDFInfo
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- CN104801805B CN104801805B CN201510203922.7A CN201510203922A CN104801805B CN 104801805 B CN104801805 B CN 104801805B CN 201510203922 A CN201510203922 A CN 201510203922A CN 104801805 B CN104801805 B CN 104801805B
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- Prior art keywords
- knife rest
- hard alloy
- solder
- stainless steel
- alloy
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Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K1/00—Soldering, e.g. brazing, or unsoldering
- B23K1/008—Soldering within a furnace
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K1/00—Soldering, e.g. brazing, or unsoldering
- B23K1/0008—Soldering, e.g. brazing, or unsoldering specially adapted for particular articles or work
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K1/00—Soldering, e.g. brazing, or unsoldering
- B23K1/19—Soldering, e.g. brazing, or unsoldering taking account of the properties of the materials to be soldered
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K1/00—Soldering, e.g. brazing, or unsoldering
- B23K1/20—Preliminary treatment of work or areas to be soldered, e.g. in respect of a galvanic coating
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K1/00—Soldering, e.g. brazing, or unsoldering
- B23K1/20—Preliminary treatment of work or areas to be soldered, e.g. in respect of a galvanic coating
- B23K1/203—Fluxing, i.e. applying flux onto surfaces
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K1/00—Soldering, e.g. brazing, or unsoldering
- B23K1/20—Preliminary treatment of work or areas to be soldered, e.g. in respect of a galvanic coating
- B23K1/206—Cleaning
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K2103/00—Materials to be soldered, welded or cut
- B23K2103/18—Dissimilar materials
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Materials Engineering (AREA)
- Ceramic Products (AREA)
Abstract
A kind of high-temp soldering method between multi-disc hard alloy and strip stainless steel knife rest, by 304 stainless steels, the sheet solder of hard alloy and middle folder transition metal is ready to, stainless steel knife rest is got rid of with sand paper, hard alloy and the oxide layer on solder surface, with acetone cleaning soldering surface, solder and transition zone alloy, then knife rest and hard metal tip face to be connected are all coated into brazing flux, solder is placed between steel knife frame and hard alloy, every hard alloy is fixed on knife rest respectively with fixture, closed be passed through in the batch-type furnace of technical argon is then placed in heat, insulation, then furnace cooling is to room temperature, take out workpiece, lay down fixture.Because alloy sheet is more, because thermal expansion factor difference there occurs flexural deformation after the welding of strip cutter hub, cold pressing correction deformation can damage hard metal tip by pressure;Therefore the cutter welded is heated to 450 DEG C, is incubated 5 minutes, directly taken out hot pressing and eliminate welding deformation, obtain the product that shape is regular, bonding strength is good.
Description
Technical field
The present invention relates to the high-temp soldering method between a kind of multi-disc hard alloy and strip stainless steel knife rest.
Background technology
Hard alloy has very high hardness, intensity, wearability and corrosion resistance, be usually used in manufacture cutting element, cutter,
Cobalt has and wear-resisting spare part, but hard alloy fragility is big, it is impossible to carry out machining, it is difficult to complex-shaped overall knife is made
Tool, thus blade of different shapes is often made, it is arranged on using the method such as welding, bonding, mechanical grip on knife rest or mold
Use.Knife rest is usually medium carbon steel, high-strength steel and stainless steel etc..Stainless steel knife rest is adapted to make under the environment for requiring corrosion-resistant
With the instrument that such as mine, field are used.Soldering is using the relatively low solder of fusing point, brazing filler metal melts but workpiece is non-fusible, profit after heating
Liquid solder wetted workpieces are used, interface gaps is filled and realizes interatomic phase counterdiffusion with workpiece, so as to realize welding, especially
It is adapted to the welding between hard alloy and knife rest.When the longer weld seam of soldering work piece solder side(More than 12.7mm), the longer thickness of knife rest
When spending little, because the linear expansion coefficient of hard alloy is 6 × 10-6Mm/ DEG C, the linear expansion coefficients of austenite steel for 16 ×
10-6Mm/ DEG C, there is very big difference in both, and very big stress is produced when making to cool down after welding, according to method for welding
Improper, process control is lack of standardization, prevents the stress intensity produced when being cooled down after welding from effectively being reduced, causes workpiece to produce
The shape that changes even ftractures.Using linear expansion coefficient(8×10-6mm/ ℃)Intermediate layer between hard alloy and knife rest can
To alleviate welding stress, Reducing distortion obtains qualified workpiece.
The content of the invention
The purpose of the present invention exactly provides a kind of multi-disc hard for the weak point in the presence of above-mentioned prior art
High-temp soldering method between alloy and strip stainless steel knife rest, for solve multi-disc welding when assembling, weld strength, weld it is curved
The problems such as song deformation is with correction.
The purpose of the present invention is realized by step in detail below:
High-temp soldering method between the multi-disc hard alloy and strip stainless steel knife rest of the present invention is comprised the following steps that:
A. prepare, obtain finished product raw material:Hard alloy is YG8;Knife rest material is stainless steel;Sheet solder composition weight
Measuring percentage is:Ag 45%, Cu 30%, surplus are Zn;Transition metal is thickness 0.05mm 1J50 Alloy Foils;Outside knife rest
Sightseeing clean, sheet solder and transition metal surfacing, it is ensured that face of weld assembling is uniform;
B., knife rest, hard alloy, sheet solder and transition metal surface scale are removed to clean, sheet solder and mistake
Cross layer metal and be cut into corresponding size by joint face size;
C. sheet solder and surface to be welded cleaned with alcohol or acetone, dried;By brazing flux QJ-308 be uniformly coated in knife rest and
Hard alloy surface to be welded;
D. sheet solder, transition metal are laid on the knife rest for coating solder flux successively, place hard metal tip, protected
Demonstrate,prove transition metal to be located in the middle of solder, solder and knife rest, hard alloy contact are fixed, the stress of fixture will with fixture
Uniformly, it is ensured that the smooth alignment of connecting end surface, unnecessary brazing flux is wiped;
E. the weldment fixed is put into closed protection air-box type stove, is passed through the air in argon gas, discharge stove, closes
Drain tap;Furnace pressure < 0.02MPa, set firing rate as 8 DEG C/min, and brazing temperature is 880 DEG C, is incubated 20 minutes,
Furnace cooling removes fixture and obtains weldment to room temperature;
F. weldment surface is removed totally, is put into chamber type electric resistance furnace, be heated to 450 DEG C and be incubated 5 minutes, directly take out hot pressing
Welding deformation is eliminated, the product that shape is regular, bonding strength is good is obtained.
Sheet solder of the present invention uses three-decker, and one layer of transition is added in the middle of every two adjacent sheet solder layers
Layer metal.
Beneficial effects of the present invention are as follows:
(1)Using the solder for adding transition zone, transition zone can alleviate absorption due to hard alloy and stainless steel linear expansion coefficient
Stress and deformation that difference is caused.
(2)Using closed chamber type electric resistance furnace, lead to protection gas heating soldering, joint brazing quality is good, intensity is high, once may be used
The multiple workpiece of soldering, efficiency high, steady quality.
(3)By heating correction, hard metal tip will not be damaged, residual deformation is eliminated, it is ensured that the shape of tool meets technology
It is required that.
Brief description of the drawings
Tri- hard alloy of Fig. 1 and the structure chart of stainless steel soldering.
Fig. 2 is Fig. 1 side view.
The structure chart of the soldering of eight hard alloy of Fig. 3 and 304 stainless steels.
Fig. 4 is Fig. 3 side view.
Sequence number in figure:1 is weld seam, and 2 be hard alloy, and 3 be knife rest.
Embodiment
The present invention is below with reference to embodiment(Accompanying drawing)It is further described:
High-temp soldering method between the multi-disc hard alloy and strip stainless steel knife rest of the present invention is comprised the following steps that:
A. prepare, obtain finished product raw material:Hard alloy is YG8;Knife rest material is stainless steel;Sheet solder composition weight
Measuring percentage is:Ag 45%, Cu 30%, surplus are Zn;Transition metal is thickness 0.05mm 1J50 Alloy Foils;Outside knife rest
Sightseeing clean, sheet solder and transition metal surfacing, it is ensured that face of weld assembling is uniform;
B., knife rest, hard alloy, sheet solder and transition metal surface scale are removed to clean, sheet solder and mistake
Cross layer metal and be cut into corresponding size by joint face size;
C. sheet solder and surface to be welded cleaned with alcohol or acetone, dried;By brazing flux QJ-308 be uniformly coated in knife rest and
Hard alloy surface to be welded;
D. sheet solder, transition metal are laid on the knife rest for coating solder flux successively, place hard metal tip, protected
Demonstrate,prove transition metal to be located in the middle of solder, solder and knife rest, hard alloy contact are fixed, the stress of fixture will with fixture
Uniformly, it is ensured that the smooth alignment of connecting end surface, unnecessary brazing flux is wiped;
E. the weldment fixed is put into closed protection air-box type stove, is passed through the air in argon gas, discharge stove, closes
Drain tap;Furnace pressure < 0.02MPa, set firing rate as 8 DEG C/min, and brazing temperature is 880 DEG C, is incubated 20 minutes,
Furnace cooling removes fixture and obtains weldment to room temperature;
F. weldment surface is removed totally, is put into chamber type electric resistance furnace, be heated to 450 DEG C and be incubated 5 minutes, directly take out hot pressing
Welding deformation is eliminated, the product that shape is regular, bonding strength is good is obtained.
Sheet solder of the present invention uses three-decker, and one layer of transition is added in the middle of every two adjacent sheet solder layers
Layer metal.
Embodiment 1:
The soldering of three hard alloy and stainless steel knife rest:Fixed using fixture shown in Fig. 1, Fig. 2, use SX2-12-11G casees
Formula special atmosphere oven entirety heating soldering, is comprised the following steps that:
A. knife rest selects model 1Cr18Ni9Ti austenitic stainless steels, is shaped as 6 × 30 × 135 rectangles, and hard is closed
Gold is tested from YG8 hard alloy, and every hard alloy size is 3 × 12 × 45;
B. sheet solder composition by weight percent is:Ag 45%, Cu 30%, surplus are Zn;Transition metal is from thick
0.05mm 1J50 Alloy Foils are spent, the model QJ-308 of brazing flux checks the presentation quality of raw material;
C. 1Cr18Ni9Ti stainless steels, carbide surface oxide-film are ground off using sand paper, to improve the quality of welding;
D. by each material surface after polishing, solder and transition zone alcohol washes, dry.Brazing flux is uniformly coated in knife
On frame and hard alloy surface to be welded;
E. sheet solder and transition zone are placed in the cutter saddle trough of polishing cleaning, place hard metal tip, entered with fixture
Row is fixed, and the stress of fixture is uniform, elastic appropriate;
F. the weldment fixed is put into SX2-12-11G box type protective atmosphere stoves, closes fire door, furnace pressure <
0.02MPa, sets firing rate as 8 DEG C/min, is always heated to 960 DEG C of welding temperature, is incubated 20min, furnace cooling to room
Temperature, obtains weldment;
G. weldment is removed from fixture, wire brushing weldment surface is reentered into stove, firing rate is 10
DEG C/min, 450 DEG C are always heated to, 5min is incubated, fire door is opened, workpiece hot pressing correction soldering on small hydraulic machine is taken out and draws
The flexural deformation risen;
H. the weldment being prepared, welding deformation is small, is conducive to hot pressing to correct, bright and clean attractive in appearance after overall blasting treatment, knife
Tool is straight and upright, and service life exceedes design requirement.
Embodiment 2:
The soldering of eight hard alloy and stainless steel knife rest:Hard alloy selects YG8 hard alloy, wherein 4 big
Hard alloy size is that 3 × 22 × 45,4 small hard alloy sizes are 3 × 10 × 45, and weldment as shown in Figure 3, Figure 4, is used
SX2-12-11G box type protective atmospheres stove entirety heating soldering, is comprised the following steps that:
A. knife rest selects the austenitic stainless steel of model 304, and hard alloy is tested from YG8 hard alloy;
B. sheet solder composition by weight percent is:Ag 45%, Cu 30%, surplus are Zn;Transition metal is from thick
0.05mm 1J50 Alloy Foils are spent, the model QJ-308 of brazing flux checks the presentation quality of raw material;
C. 304 stainless steels, carbide surface oxide-film are ground off using sand paper, to improve the quality of welding.
D. by each material surface after polishing, solder and transition zone alcohol washes, dry.Brazing flux is uniformly coated in knife
On frame and hard alloy surface to be welded.
E. sheet solder and transition zone are placed in the cutter saddle trough of polishing cleaning, place hard metal tip, entered with fixture
Row is fixed, and the stress of fixture is uniform, elastic appropriate;
F. the weldment fixed is put into SX2-12-11G box type protective atmosphere stoves, closes fire door, furnace pressure <
0.02MPa, sets firing rate as 8 DEG C/min, is always heated to 880 DEG C of welding temperature, is incubated 20min, furnace cooling to room
Temperature, obtains weldment;
G. weldment is removed from fixture, wire brushing weldment surface is reentered into stove, firing rate is 10
DEG C/min, 450 DEG C are always heated to, 5min is incubated, fire door is opened, workpiece hot pressing correction soldering on small hydraulic machine is taken out and draws
The flexural deformation risen;
H. the weldment being prepared, welding deformation is small, is conducive to hot pressing to correct, bright and clean attractive in appearance after overall blasting treatment, knife
Tool is straight and upright, and service life exceedes design requirement.
Claims (2)
1. the high-temp soldering method between a kind of multi-disc hard alloy and strip stainless steel knife rest, it is characterised in that:The method for welding
Comprise the following steps that:
A. prepare, obtain finished product raw material:Hard alloy is YG8;Knife rest material is stainless steel;Sheet solder Ingredients Weight hundred
Point ratio is:Ag 45%, Cu 30%, surplus are Zn;Transition metal is thickness 0.05mm 1J50 Alloy Foils;Gone sightseeing outside knife rest
It is clean, sheet solder and transition metal surfacing, it is ensured that face of weld assembling is uniform;
B., knife rest, hard alloy, sheet solder and transition metal surface scale are removed to clean, sheet solder and transition zone
Metal is cut into corresponding size by joint face size;
C. sheet solder and surface to be welded cleaned with alcohol or acetone, dried;Brazing flux QJ-308 is uniformly coated in knife rest and hard
Alloy surface to be welded;
D. sheet solder, transition metal are laid on the knife rest for coating solder flux successively, place hard metal tip, it is ensured that mistake
Layer metal is crossed in the middle of solder, solder and knife rest, hard alloy contact are fixed, the stress of fixture is uniform with fixture,
Ensure the smooth alignment of connecting end surface, wipe unnecessary brazing flux;
E. the weldment fixed is put into closed protection air-box type stove, is passed through the air in argon gas, discharge stove, closes exhaust
Valve;Furnace pressure < 0.02MPa, set firing rate as 8 DEG C/min, and brazing temperature is 880 DEG C~960 DEG C, is incubated 20 points
Clock, furnace cooling removes fixture and obtains weldment to room temperature;
F. weldment surface is removed totally, is put into chamber type electric resistance furnace, be heated to 450 DEG C and be incubated 5 minutes, directly take out hot pressing elimination
Welding deformation, obtains the product that shape is regular, bonding strength is good.
2. the high-temp soldering method between multi-disc hard alloy according to claim 1 and strip stainless steel knife rest, its feature
It is:The sheet solder uses three-decker, and one layer of transition metal is added in the middle of every two adjacent sheet solder layers.
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CN105364244B (en) * | 2015-12-21 | 2017-10-27 | 株洲通达合金股份有限公司 | A kind of welding method of hard alloy and stainless steel compound bar pin |
CN108858306B (en) * | 2018-05-30 | 2021-02-19 | 马鞍山市威马机械设备有限责任公司 | Processing method of strip paper cutting alloy blade |
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CN110216343A (en) * | 2019-07-17 | 2019-09-10 | 无锡市宝赛德机械制造有限公司 | The production technology of carbide bit |
CN110883443A (en) * | 2019-12-12 | 2020-03-17 | 郑州机械研究所有限公司 | Hard alloy brazing joint, preparation method thereof and hard alloy tool |
CN111037021B (en) * | 2020-01-13 | 2021-01-05 | 郑州机械研究所有限公司 | Resistance brazing method for shield machine cutter |
CN113102854B (en) * | 2021-03-29 | 2022-11-15 | 浙江浪潮精密机械有限公司 | Automatic continuous brazing device and method for hard alloy cutter |
CN113399858A (en) * | 2021-04-25 | 2021-09-17 | 郑州机械研究所有限公司 | Composite brazing filler metal for brazing, preparation method thereof and hard alloy cutter |
CN113245655B (en) * | 2021-06-28 | 2021-10-29 | 东北大学 | Hard alloy/steel porous compensation net reinforced soldered joint and preparation method thereof |
CN113579386B (en) * | 2021-08-12 | 2023-02-21 | 郑州机械研究所有限公司 | Brazing flux-free brazing method for hard alloy cutter |
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CN1218809C (en) * | 2003-06-10 | 2005-09-14 | 李嘉珍 | High-strength silver-base brazing alloy and use thereof |
CN102922154B (en) * | 2012-11-29 | 2014-07-30 | 西安科技大学 | Soldering/diffusion welding hybrid welding method for cemented carbide and alloy steel |
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