CN103056355B - Manufacturing and application methods for laser cladding powder of iron-base alloy - Google Patents

Abstract

The invention discloses a design manufacturing method and an application method for laser cladding powder. The design manufacturing method includes preparing Fe-Mn-Si memory alloy powder and putting the memory alloy powder into a ball grinder to process powder mixing. The application method includes processing a vacuum drying treatment before the cladding, presetting the cladding powder on base materials, and processing the cladding with laser which is 1.5-3 Kw in laser power, 400-1000 mm / min in scanning speed and 3 mm in laser diameter. By the stress of the laser cladding layer of the Fe-Mn-Si memory alloy, martensitic transformation and the martensitic deformation compatibility are induced so as to effectively remove the residual stress of the cladding layer and improve the fatigue strength of the cladding layer with no need of adding extra processing. The laser cladding powder of the iron-base alloy has the advantages of being simple in preparation technology, applicable to mass production, good in wear resistance, low in residual stress, high in fatigue strength, and the like.

Description

A kind of manufacture of Laser Cladding of Iron-based Alloy powder and using method thereof

Technical field

Patent of the present invention relates to laser melting and coating technique, particularly a kind of manufacture of Laser Cladding of Iron-based Alloy powder and using method thereof.

Background technology

Laser melting coating refers to, by different adding material modes, selected coating material is placed on coated matrix surface, through high-energy-density laser beam irradiation, make it to melt with matrix surface thin layer simultaneously, and rapid solidification formation dilution rate is extremely low, and be the face coat of metallurgical binding with matrix material, thus significantly improve the process of metal surface performance.Utilize the laser cladding layer of industrial conventional ferrous alloy cladding powder gained can have higher hardness, wearability at present, but in fast melt and process of setting, cladding layer can produce residual-tensile stress due to the reason of thermal contraction, make cladding layer decrease of fatigue strength, even produce microcosmic and macroscopic cracking.The main method of current reduction cladding layer residual stress has reduction thermograde, in cladding material, adds plasticising, toughness reinforcing element, ultrasonic wave vibration etc., but these methods all need to increase additional process, considerably increase cost, and these methods can not stop the generation of crackle completely, lack corresponding theoretical breakthrough.

Summary of the invention

For solving the problems referred to above that prior art exists, the object of the invention is to provide a kind of increase additional process that do not need can effectively eliminate cladding layer residual stress and improve Laser Cladding of Iron-based Alloy powder and the using method thereof of cladding layer fatigue strength.

To achieve these goals, technical scheme of the present invention comprises a kind of design and production method of Laser Cladding of Iron-based Alloy powder and a kind of Laser Cladding of Iron-based Alloy powder using method.

A design and production method for laser cladding powder, comprises the following steps:

A, preparation powder

Iron based laser cladding power formulations builds method preparation that laser cladding layer forms for Fe-Mn-Si memory alloy composition, namely by following mass percent preparation Laser Cladding of Iron-based Alloy powder:

Mn powder: 15% ~ 25%;

Si powder: 2% ~ 10%;

Cr powder: 1% ~ 13%;

Ni powder: 1% ~ 12%;

V powder: 0 ~ 2%;

Nb powder: 0 ~ 2%;

Ti powder: 0 ~ 2%;

Zr powder: 0 ~ 2%;

Rare earth: 0 ~ 3%;

Quartz: 0 ~ 5%;

Wood powder: 0 ~ 3%;

Starch: 0 ~ 5%;

All the other are pure iron Fe powder or contain C0.1% ~ 0.4% mild steel powder;

The purity of above-mentioned powder be analyze pure;

B, powder mix

Pour ball mill for dry grinding 2 ~ 8h into after being weighed by above-mentioned powder, make the order Task-size Controlling of mixed-powder between 120 ~ 320 orders.

A using method for Laser Cladding of Iron-based Alloy powder, comprises the following steps:

A, cladding powder is carried out to temperature is 150 DEG C, the time is the vacuum drying treatment of 2h before cladding;

B, be preset in base material on as binding agent by cladding powder with waterglass, pre-set thickness controls at 1 ~ 2mm;

C, be 1.5 ~ 3kW by laser power, sweep speed is 400 ~ 1000mm/min, spot diameter is 3mm laser carries out cladding.

Compared with prior art, the present invention has following beneficial effect:

1, iron based laser cladding material of the present invention utilizes the stress-induced of Fe-Mn-Si memorial alloy laser cladding layer martensitic traoformation and compatibility of deformation thereof are eliminated cladding layer residual stress and are improved cladding layer fatigue strength, do not need to increase additional process and effectively can eliminate cladding layer residual stress and effectively improve cladding layer fatigue strength.

2, Laser Cladding of Iron-based Alloy powder process of the present invention is simple, is suitable for bulk industrial and produces.

3, the clad layer surface that obtains of Laser Cladding of Iron-based Alloy powder of the present invention is smooth, bright, and without the defect such as hole, crackle, cladding layer comprehensive mechanical property is excellent, especially has the feature that wearability is good, residual stress is low, fatigue strength is high.

Accompanying drawing explanation

The present invention has 4, accompanying drawing, wherein:

Fig. 1 is the polishing scratch figure under 50kg pressure after Fe-17Mn-5Si-10Cr-4Ni alloy oil abrasion 585min.

Fig. 2 is the polishing scratch figure after 1Cr18Ni9Ti stainless steel oil abrasion 15min.

Fig. 3 is the metallograph of cladding layer of the present invention.

Fig. 4 is the X-ray diffraction spectrum of cladding layer of the present invention.

Detailed description of the invention

Below in conjunction with drawings and Examples, the present invention and beneficial effect are described further.Because the present invention adopts Fe-Mn-Si memorial alloy powder as laser cladding powder, it is that the residual-tensile stress of cladding layer can make alloy bring out γ → ε martensitic traoformation that Fe-Mn-Si memorial alloy cladding layer reduces the mechanism of weld residual stress, its phase transformation distortion (expansion), by the residual-tensile stress of lax cladding layer, makes it be reduced to (because induced phase transition driving force is lower than yield strength) under yield strength; The method that Fe-Mn-Si memorial alloy cladding layer improves cladding layer fatigue strength is based on its " stress adaptive characteristic ", namely, when alloy is subject to extraneous effect of stress, the change adapting to extraneous macro-stress and distortion is out of shape in the phase transformation by the positive reverse transformation of stress-inducedεmartensite and contribution thereof.The stress " adaptive characteristic " of Fe-Mn-Si memorial alloy can improve its mechanical property greatly.Be mainly manifested in following two aspects:

1, excellent strain fatigue strength

There is selecting to when moving of Shockley imperfect dislocation in Fe-Mn-Si memorial alloy, namely produce under mechanical force drives during martensitic traoformation distortion, crystal structure can not be destroyed as the distortion of perfect dislocation plastic flow.Therefore, Fe-Mn-Si memorial alloy is (ε <3%) in the strain level that phase transformation is out of shape, and has higher fatigue strength.Such as, the cyclic strain fatigue life of Fe-17Mn-5Si-10Cr-4Ni alloy under tension and compression plastic strain amplitude ± 1.5% is up to more than 1300 times, and under same experimental condition, 70Mn rail steel and stainless low-cycle fatigue life are respectively 110 times and 130 times.

2, good wearability and high surfaces contact fatigue strength

Fe-Mn-Si memorial alloy is in process of friction and wear, and " the phase transformation strengthening effect " that caused by the phase transformation of friction stree strain induced martensite and " phase transformation distortion ", can significantly improve its surface contact fatigue stress and wear resistance.Fig. 1, Fig. 2 have showed the quality of Fe-17Mn-5Si-10Cr-4Ni alloy and 1Cr18Ni9Ti stainless steel wearability intuitively.

Embodiment of the present invention manufactures Fe-Mn-Si memorial alloy laser cladding coating at AISI304 stainless steel surfaces, and concrete steps are as follows.

A, powder mixture ratio

According to materials such as design Analysis about Selection straight iron powder, nickel powder, manganese powder, silica flour, chromium powder, vanadium powders, for improving powder and cladding layer capability, suitably add the materials such as rare earth, quartz, wood powder, starch.One of food ingredient mass percent these following three kinds:

1# fills a prescription: manganese powder: 17%, silica flour: 5%, chromium powder: 10%, nickel powder: 5%, vanadium powder: 0.5%, quartz: 2%, wood powder: 2.5%, starch: 3%, and after removing impurity, all the other compositions are straight iron powder;

2# fills a prescription: Mn powder: 15%, Si powder: 3%, Cr powder: 9%, Ni powder: 4%, Nb powder: 1%, quartz: 2%, and all the other are C content 0.2% mild steel powder;

3# fills a prescription: Mn powder: 20%, Si powder: 5%, Cr powder: 10%, Ni powder: 4%, Ti powder: 0.5%, wood powder: 1%, starch: 1%, all the other are pure iron Fe powder.

B, ball milling

The powder that proportioning is good is poured in ball mill, Ball-milling Time is long or too short all can not ensure that powder can mix, there is again good mobility, order granularity.Test shows: the mixed-powder excellent performance when Ball-milling Time is 2 ~ 8h.

C, laser melting coating

Need to carry out 150 DEG C, 2h vacuum drying treatment to cladding powder before cladding, be preset in base material on as binding agent by powder with waterglass again, pre-set thickness controls at 1 ~ 2mm, and during cladding, laser power is 1.5 ~ 3kW, sweep speed is 400 ~ 1000mm/min, and spot diameter is 3mm.

Fig. 3 is the metallograph of Fe-Mn-Si memorial alloy laser cladding layer of the present invention.Fig. 4 is the X-ray diffraction spectrum of Fe-Mn-Si memorial alloy laser cladding layer of the present invention.As seen from Figure 4, there is ε martensitic traoformation in Fe-Mn-Si memorial alloy laser cladding layer, show that cladding layer there occurs stress-inducedεmartensite under residual stress effect, the residual stress of the laser cladding layer that can relax is out of shape in phase transformation.

Claims (1)

1. a design and production method for laser cladding powder, is characterized in that: comprise the following steps:

A, preparation powder

Iron based laser cladding power formulations builds method preparation that laser cladding layer forms for Fe-Mn-Si memory alloy composition, namely by following mass percent preparation Laser Cladding of Iron-based Alloy powder:

Mn powder: 15% ~ 25%;

Si powder: 2% ~ 10%;

Cr powder: 1% ~ 13%;

Ni powder: 1% ~ 12%;

V powder: 0 ~ 2%;

Nb powder: 0 ~ 2%;

Ti powder: 0 ~ 2%;

Zr powder: 0 ~ 2%;

Rare earth: 0 ~ 3%;

Quartz: 0 ~ 5%;

Wood powder: 0 ~ 3%;

Starch: 0 ~ 5%;

All the other are pure iron Fe powder or contain C0.1% ~ 0.4% mild steel powder;

The purity of above-mentioned powder be analyze pure;

B, powder mix

Pour ball mill for dry grinding 2 ~ 8h into after being weighed by above-mentioned powder, make the order Task-size Controlling of mixed-powder between 120 ~ 320 orders.