CN109100387A - A method of heat flow density when measurement high energy beam impact plane - Google Patents

A method of heat flow density when measurement high energy beam impact plane Download PDF

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CN109100387A
CN109100387A CN201810860524.6A CN201810860524A CN109100387A CN 109100387 A CN109100387 A CN 109100387A CN 201810860524 A CN201810860524 A CN 201810860524A CN 109100387 A CN109100387 A CN 109100387A
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energy beam
heat flux
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余德平
段亚洲
徐继业
邱吉尔
李磊
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Sichuan University
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Abstract

本发明公开了一种测定高能束冲击平面时热流密度的方法。根据高能束在空气中传播时，截面热流密度大致遵循高斯分布的特性，当高能束作用于铁基材料一段时间后，材料会产生月牙形相变硬化，此月牙形相变区域的尺寸能直接反映出高能束的热流密度分布规律。通过仿真软件拟合，并调整系数得到相同相变区，进而将系数带入热流密度分布公式中，可得到截面热流密度分布。该发明所述方法，操作简单，无需专用接收靶板；能够得到连续的热流密度分布方程；且适用范围广极广。

The invention discloses a method for measuring the heat flux density when a high-energy beam hits a plane. According to the characteristic that the cross-sectional heat flux roughly follows the Gaussian distribution when the high-energy beam propagates in the air, when the high-energy beam acts on the iron-based material for a period of time, the material will undergo crescent-shaped phase transition hardening, and the size of the crescent-shaped phase transition region can be directly It reflects the heat flux distribution law of the high-energy beam. Fitting by simulation software, and adjusting the coefficients to obtain the same phase change region, and then bringing the coefficients into the heat flux distribution formula, the cross-sectional heat flux distribution can be obtained. The method described in the invention is simple to operate, does not need a special receiving target plate; can obtain a continuous heat flux distribution equation; and has a wide range of applications.

Description

A method of heat flow density when measurement high energy beam impact plane
Technical field
The present invention relates to a kind of methods of heat flow density when measurement high energy beam impact plane.
Background technique
High energy beam, is often referred to laser, electron beam and ion beam, common trait be supplied with the power density of material surface >= 103w/cm2.With the upgrading of traditional manufacture, high energy beam processing has become one of modern manufacturing technology the most advanced, is praised For " processing of 21 century ".Because it is high with power density, action time is short, heating process is contactless, controllability is good And the comprehensive advantages such as environmental-friendly, high energy beam processing is increasingly becoming the key technology for developing high, precision and frontier weaponry, in industry Proportion is also increasing, and then becomes one of the important indicator for measuring a National Industrial manufacture level.High energy beam processing Field is even more to cover the various aspects such as welding, cutting, etching, surface modified, spraying and vapor deposition, aerospace, The numerous areas such as ship, weapons, nuclear energy, traffic, medical treatment play an important role.
The quality and application development of high energy beam processing and the quality of beam of high energy beam are closely related, and quality of beam mainly has two Aspect intension: first is that stability, second is that the form and Energy distribution of line.Therefore, pass through cutting apart from spout difference to line Face carries out heat flow density measurement when impacting plane, and then analyzes beam status and whether Energy distribution good, to working ability and The raising of processing quality suffers from particularly important effect, still, due to the energy and extreme temperatures of high energy beam, it is difficult to using straight The mode for connecing measurement accurately obtains the regularity of distribution of its heat flow density.
Summary of the invention
The invention proposes a kind of application material surface transformation hardenings, are existed by testing and emulating fitting with measuring high energy beam The method of heat flux distribution when particular cross section impacts plane.
It is small with the decreasing gradient in axial direction that the distinguishing feature of high energy beam is that its heat flow density is uniformly distributed radially.It is special Point is that the heat flux distribution form in any section of high energy beam is typically all Gaussian distributed.It is expressed as follows with formula 1-1:
(1-1)
In formula, qHmIt is maximum heat flow density, r is the distance apart from hot spot center, and total thermal energy (Q) is expressed as in the hot spot of section Formula 1-2:
(1-2)
Therefore,
(1-3)
The 95% of total heat energy (Q) will be concentrated in this hot spot, and therefore, the relational expression of Q and k can be expressed as formula 1-4:
(1-4)
Simplified style 1-4 can be obtained:
(1-5)
Q be it is relevant to high energy beam input power, formula 1-6 can be expressed as:
(1-6)
P is the input power of high energy beam in formula, β be one with heat loss (due to the cooling system and generator spout of high energy beam At a distance from substrate surface) relevant coefficient, η is thermal absorptivity, it is related with the thermal physical property parameter of substrate.
Simultaneous 1-3,1-5,1-6 Shi Ke get Shi 1-7 are as follows:
(1-7)
It is calculated to simplify, reduces the number of unknown quantity, using a corresponding constant coefficient δ, and the expression formula of δ is formula 1-8:
(1-8)
Therefore, qH(r) formula 1-9 can be expressed as:
(1-9)
After high energy beam acts on iron-based material for a period of time, material can generate crescent transformation hardening, hot shadow obtained The size for ringing area can directly reflect the heat flux distribution rule of high energy beam.Based on this principle, by being set in numerical simulation It sets and tests identical technological parameter, and regulation coefficient obtains identical phase change zone, and then brings coefficient into heat flux distribution public affairs In formula (1-9), section heat flux distribution can be obtained.
Its specific determination step is as follows:
Step 1: selecting a kind of iron-based material, be processed as the standard shape of setting as substrate, substrate surface and high energy beam are sent out The distance of raw device spout is adjusted to vertical range d=1 ~ 500mm, is then set as scanning speed substrate surface will not be enabled to generate Speed 10mm/min ~ 3000mm/min of fusing, then carry out single track quench hardening operation;
Step 2: substrate being cut along hardening section, after sanding and polishing corrodes, observes hardening zone size (width under the microscope W and depth D);
Step 3: setting initial parameterδWith rH,δFor coefficient relevant to the thermal efficiency, substrate type, vertical range d, range exists Between 0.1 ~ 0.7, rHInitial value be hardening zone width D；
Step 4: numerical simulation being carried out to hardening process using finite element software, setting simulation parameter is to test technique ginseng used Number marks off simulation hardening zone according to the critical-temperature that austenitizing occurs for material, and obtains the width W of simulation hardening zone1With Depth D1;
Step 5: adjustmentδWith rHSo that simulate the width W of hardening zone1With depth D1With the width W and depth D ruler of practical hardening zone It is very little roughly the same；
Step 6: willδWith rHBring formula intoIn (P is power, and r is away from round spot centre distance) High energy beam is obtained in the heat flux distribution at spout d.
A kind of method measuring high energy beam heat flow density of the present invention has the advantage that
1. it is easy to operate, it is not necessarily to dedicated reception target plate.Mark due to the hardening zone using iron-based material as measurement heat flow density Standard only needs common iron-based material as substrate, pops one's head in without making dedicated reception target plate and installing profession on target plate.Experiment Process is simple to operation, due to not needing arrangement probe, avoids because of the error generated by inconsistency of popping one's head in, and continuous mode Required cost is less；
2. continuous heat flux distribution equation can be obtained.The heat affected area being fitted by finite element simulation, with practical hardening Area's comparison, obtained parameter value is substituted into formula, available complete continuity equation；
3. applied widely.Measuring method of the present invention is widely applicable for various high-energy fluids, need to only adjust substrate kind Class and scanning speed can obtain hardening zone, and further Curve fitting simulation obtains heat flux distribution.
Detailed description of the invention
Fig. 1 is high energy beam generator and matrix structure figure to be quenched, wherein (1) is plasma generator, (2) are substrates, It (3) is plasma flame flow；
Fig. 2 is embodiment working drawing；
Fig. 3 is heat affected area detection sectional plane figure；
Fig. 4 is heat affected area emulation sectional view.
Specific embodiment
The method of heat flow density is made further when by the following examples to measurement high energy beam impact plane of the present invention Explanation.
Embodiment one
Using plasma as high energy beam, U75V is substrate (having a size of 200 × 100 × 15 mm), such as with plasma generator by substrate Position shown in Fig. 1 is fixed, distance d be 4mm, open plasma generator, input power is 11.3 kW, and make its with speed v= 900mm/min scans substrate surface, after its natural cooling, cuts substrate along hardening section, after sanding and polishing corrodes, Hardening zone size, width W=10.3mm, depth D=1.5mm are observed under microscope.Carry out finite element simulation, adjustmentδWith rHMake to imitate The width W of heat affected area in true result1=10mm ≈ W=10.3mm, D1=1.5 ≈ D=1.5mm, obtainδWith rHRespectively 0.67 with 9.5, heat flux distribution are as follows:(r is away from round spot center).
Embodiment two
Using plasma as high energy beam, U75V is substrate (having a size of 200 × 100 × 15 mm), such as with plasma generator by substrate Position shown in Fig. 1 is fixed, distance d be 10mm, open plasma generator, input power is 11.3 kW, and make its with speed v= 800mm/min scans substrate surface, after its natural cooling, cuts substrate along hardening section, after sanding and polishing corrodes, Hardening zone size, width W=8.2mm, depth D=1.1mm are observed under microscope.Carry out finite element simulation, adjustmentδWith rHMake to emulate As a result the width W of middle heat affected area1=8.6mm ≈ W, D1=1.1 ≈ D, obtainδWith rHRespectively 0.42 and 8.1, heat flow density point Cloth are as follows:(r is away from round spot center).
Embodiment three
Using plasma as high energy beam, U75V is substrate (having a size of 200 × 100 × 15 mm), such as with plasma generator by substrate Position shown in Fig. 1 is fixed, distance d be 20mm, open plasma generator, input power is 11.3 kW, and make its with speed v= 650mm/min scans substrate surface, after its natural cooling, cuts substrate along hardening section, after sanding and polishing corrodes, Hardening zone size, width W=6mm, depth D=0.6mm are observed under microscope.Carry out finite element simulation, adjustmentδWith rHTie emulation The width W of heat affected area in fruit1=5.8mm ≈ W, D1=0.7 ≈ D, obtainsδWith rHRespectively 0.18 and 6.2, heat flux distribution Are as follows:(r is away from round spot center).
Finally it is to be appreciated that the above case study on implementation is only used to illustrate the technical scheme of the present invention rather than limits, this field skill Art personnel should be appreciated that technical solution of the present invention modify either equivalent replacement, and be detached from spirit of the invention and Range should all cover in protection scope of the present invention.

Claims (8)

1.一种测定高能束冲击平面时热流密度的方法，其特征在于，包括以下步骤：1. a method for heat flux when measuring high-energy beam impact plane, is characterized in that, may further comprise the steps: 步骤1：选择一种铁基材料，加工为设定的标准形状作为基材，将基材表面与高能束发生器喷口的距离调整为垂直距离d=1~500mm，然后将扫描速度设定为不会令基材表面产生熔化的速度10mm/min~3000mm/min，再进行单道淬火硬化操作;Step 1: Select an iron-based material, process it into a set standard shape as the substrate, adjust the distance between the surface of the substrate and the nozzle of the high-energy beam generator to a vertical distance of d=1~500mm, and then set the scanning speed to The speed that will not cause the surface of the substrate to melt is 10mm/min~3000mm/min, and then the single-pass quenching and hardening operation is performed; 步骤2：沿硬化截面将基材切割，经打磨抛光腐蚀后，在显微镜下观测硬化区尺寸（宽度W与深度D）;Step 2: Cut the base material along the hardened section, and observe the size of the hardened zone (width W and depth D) under a microscope after grinding, polishing and corrosion; 步骤3：设定初始参数δ与rH，δ为与热效率、基材种类、垂直距离d相关的系数，范围在0.1~0.7之间，rH的初始值为硬化区宽度D；Step 3: Set the initial parameters δ and r H , δ is a coefficient related to thermal efficiency, substrate type, and vertical distance d, the range is between 0.1 and 0.7, and the initial value of r H is the width of the hardened zone D; 步骤4：使用有限元软件对硬化过程进行数值仿真，设置仿真参数为实验所用工艺参数，根据材料发生奥氏体化的临界温度划分出模拟硬化区，并得到模拟硬化区的宽度W1和深度D1;Step 4: Use finite element software to numerically simulate the hardening process, set the simulation parameters as the process parameters used in the experiment, divide the simulated hardened zone according to the critical temperature of austenitization of the material, and obtain the width W1 and depth of the simulated hardened zone D 1 ; 步骤5：调整δ与rH,使得模拟硬化区的宽度W1和深度D1与实际硬化区的宽度W和深度D尺寸大致相同;Step 5: Adjust δ and r H so that the width W 1 and depth D 1 of the simulated hardened zone are roughly the same as the width W and depth D of the actual hardened zone; 步骤6：将步骤5得到的δ与rH带入公式（P为功率，r为距圆斑中心距离）中，即可得到高能束在距离喷口d处的热流密度分布。Step 6: Bring the δ and r H obtained in Step 5 into the formula (P is the power, r is the distance from the center of the circular spot), the heat flux distribution of the high-energy beam at the distance d from the nozzle can be obtained. 2.根据权利要求1中所述测定高能束冲击平面时热流密度的方法，其特征在于：步骤1中，所述铁基材料包括并不限于45号钢、AISI 304、铸铁等常见材料。2. The method for measuring the heat flux when the high-energy beam hits the plane according to claim 1, characterized in that: in step 1, the iron-based material includes but is not limited to common materials such as No. 45 steel, AISI 304, and cast iron. 3.根据权利要求1中所述测定高能束冲击平面时热流密度的方法，其特征在于：步骤1中，所述扫描速度在10mm/min~3000mm/min。3. The method for measuring the heat flux when the high-energy beam hits the plane according to claim 1, characterized in that: in step 1, the scanning speed is 10mm/min~3000mm/min. 4.根据权利要求1中所述测定高能束冲击平面时热流密度的方法，其特征在于：步骤2中，所述观测尺寸为硬化区的宽度和深度，可以通过腐蚀后截面的颜色转变判断硬化区域。4. according to the method for heat flux density when measuring high-energy beam impact plane described in claim 1, it is characterized in that: in step 2, described observation dimension is the width and the depth of hardening zone, can judge hardening by the color change of section after corrosion area. 5.根据权利要求1中所述测定高能束冲击平面时热流密度的方法，其特征在于：步骤3中，所述δ初始值在0.1~0.7之间。5. The method for measuring the heat flux when the high-energy beam hits the plane according to claim 1, characterized in that: in step 3, the initial value of δ is between 0.1 and 0.7. 6.根据权利要求1中所述测定高能束冲击平面时热流密度的方法，其特征在于：步骤3中，所述rH初始值与硬化区宽度相同。6. The method for measuring the heat flux when the high-energy beam hits the plane according to claim 1, characterized in that: in step 3, the initial value of r H is the same as the width of the hardened zone. 7.根据权利要求1中所述测定高能束冲击平面时热流密度的方法，其特征在于：步骤4中，通过数值仿真软件（包括并不限于Ansys，Abaqus等）得到模拟宽度与深度。7. The method for measuring the heat flux when the high-energy beam hits the plane according to claim 1, characterized in that: in step 4, the simulated width and depth are obtained by numerical simulation software (including but not limited to Ansys, Abaqus, etc.). 8.根据权利要求1中所述测定高能束冲击平面时热流密度的方法，其特征在于：步骤5中，通过调整δ、rH使模拟硬化区的宽度W1和深度D1与实际硬化区的宽度W和深度D尺寸大致相同。8. according to the method for heat flux density when measuring high-energy beam impact plane described in claim 1, it is characterized in that: in step 5, make the width W 1 and depth D 1 of simulated hardened zone and actual hardened zone by adjusting δ, r H The width W and depth D dimensions are approximately the same.
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