CN106513674B - 3d print protective gas circulating forming cavity metal powder bed filtration apparatus and optimization method - Google Patents

3d print protective gas circulating forming cavity metal powder bed filtration apparatus and optimization method Download PDF

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CN106513674B
CN106513674B CN 201610835216 CN201610835216A CN106513674B CN 106513674 B CN106513674 B CN 106513674B CN 201610835216 CN201610835216 CN 201610835216 CN 201610835216 A CN201610835216 A CN 201610835216A CN 106513674 B CN106513674 B CN 106513674B
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intake
protective gas
flow
gas
split
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CN106513674A (en )
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顾冬冬
戴冬华
熊家鹏
马成龙
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南京航空航天大学
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本发明公开种3D打印金属粉末床成形腔体的保护气循环过滤装置及其优化方法,该优化方法通过调整加工烟尘竖直运动距离,使得加工烟尘竖直运动距离不大于吸气导流道的高度,进而达到加工烟尘完全被吸气导流道捕获、成形腔体中进气分流口至吸气导流口的压力逐渐减小的目的,致使本发明加工金属零件具有表面质量好,致密度高,机械性能好等特点。 The present invention discloses a powder bed of metal species 3D printing cycle molding cavity protective gas filtration apparatus and optimization method, the optimization method by adjusting the distance of vertical movement machining dust, soot processing such vertical movement distance is no greater than the intake flow passage height, thus achieving machining dust suction flow channel is completely captured, the forming cavity split intake port to the destination port pressure of the intake flow gradually decreases, so that the present invention is processed metal parts with good surface quality, density high mechanical performance and good features.

Description

3D打印金属粉末床成形腔体的保护气循环过滤装置及其优化方法 3D printing metal powder bed protective gas circulating device and a filter cavity formed Optimization

技术领域 FIELD

[0001] 本发明属于3D金属粉末打印技术领域,尤其涉及金属粉末床成形腔体保护气循环过滤系统的改进。 [0001] The present invention belongs to the field of 3D printing technology of metal powders, in particular, it relates to a metal powder bed forming cavity protective gas circulation filtering system.

背景技术 Background technique

[0002] 基于金属粉末床技术的3D打印技术因其能最大限度地不受零件复杂形状限制,能高效且低成本地制备出精度极高的复杂金属功能整体零件。 [0002] Metal powder bed based 3D printing techniques to maximize its complex shape parts without limitation, can be prepared in an efficient and cost very high precision integral features of complex metal parts. 由于金属具有强氧化性,故所制备零件都在充满惰性气体的密封成形腔中完成。 Since metals have strong oxidizing, so the parts are produced in the forming cavity filled with an inert sealing gas is completed. 但高能量激光与金属粉末短时剧烈作用时,熔化液滴具有强大不稳定性且容易产生熔滴飞溅和金属汽化,尤其是加工物理化学活性极高金属,如镁、铝和钛等,所产生烟尘将笼罩在待加工工件上方,将导致凝固金属表面污染严重:表面质量降低、层/道间润湿性降低及结合性差、零件致密度下降和失去金属光泽。 However, high-energy laser with the metal powder short intense action, melted droplets have strong instabilities and easy to produce metal droplets and splashes vaporization, in particular physico-chemical machining high activity metals, such as magnesium, aluminum, and titanium, the smoke generation will be enveloped over the workpiece, will result in severe contamination of solidified metal surface: surface quality decreases, the interlayer / reduce the wettability and the coupling channel is poor, the density decreased and the loss of parts metallic luster. 同时,该烟尘位置处于激光与金属粉末材料之间,将大大削减传至金属粉末的激光能量,造成激光能量浪费和金属粉末熔化不完全,进而导致成形件内部存在未熔金属粉末夹杂,极大地加大激光器能耗,增加了建设和发展绿色可持续制造业阻力。 Meanwhile, the dust position is between the laser material and the metal powder, the metal powder will greatly reduce the transmitted laser energy, laser energy causing melting of the metal powder waste and incomplete, leading to the presence of inner member forming a refractory metal powder inclusions not greatly increase the laser energy, increasing the manufacturing sustainable green building and development resistance.

[0003] 现有粉末床成形腔体基本都加入了保护气循环过滤装置,尽最大能力避免金属氧化或减少烟尘对加工凝固金属影响。 [0003] Existing powder bed forming cavity are basically added to the protective gas circulation filter device to maximize its ability to reduce or prevent oxidation of the metal machining dust solidified metal impact. 但腔体保护气循环过滤装置基本上都根据经验进行设计,设计人员对进气口保护气流量、压力和进气分流截面面积与成形腔体尺寸之间的内在关系还存在认识不足。 However, the protective gas circulation chamber filter device basically designed, the designer of the intake air flow protected port, the intake pressure and the intrinsic relationship between the split cross-sectional area of ​​the forming cavity size there is lack of knowledge based on experience. 所设计保护气循环过滤装置进气口流速过大,将严重影响成形基板均匀预铺粉末质量;而进气口流速过小,对加工过程形成烟尘完全没有过滤作用。 The filtering device designed to protect gas circulation flow rate is too large intake port, will seriously affect the uniformity of the substrate pre-coated powder molding mass; the air inlet flow rate is too small, soot is formed on the filtration process no. 设计者将需经历无数次循环过滤装置调试,无形加大了设计及制造成本;并且,不合理保护气循环过滤装置也很难保证制备出优异机械性能金属功能件。 The designer needs to undergo numerous cycles filter means debugging, Invisible increased design and manufacturing costs; and unreasonable protective gas circulation filtering apparatus is difficult to ensure excellent mechanical properties prepared metal member function.

[0004] 保护气循环过滤装置将直接影响粉末床成形腔体压力分布,进而对烟尘在进气分流口与吸气导流口之间的流动行为起决定作用。 [0004] The loop filter a shielding gas will directly affect the powder bed forming cavity pressure distribution, and thus the flow behavior of dust between the intake port and the intake flow diversion port play a decisive role. 粉末床成形腔体压力理想分布为:由进气分流口至吸气导流口表现为逐渐减小趋势;但目前设备腔体中基本都面临着腔体中压力梯度不可控难题,例如:腔体进气分流口“负压”现象。 Molding the powder bed over the distribution chamber pressure: flow intake port by the intake performance is to split vent which decreased; but the basic apparatus cavities are facing the pressure gradient in the cavity uncontrollable problems, for example: a chamber an intake port split body "negative" phenomenon. “负压”现象将使烟尘向进气分流口方向运动,造成烟尘在进气口堆积和多次污染已过滤保护气,严重时将引起进气口堵塞或者其他机械干涉现象。 "Negative pressure" phenomenon will cause the smoke to the intake diversion opening direction, causing smoke filtered protective gas accumulation in the intake port and multiple pollution, will cause serious air inlet blockage or other mechanical interference.

[0005] 尤其当采用该技术对大型复杂金属构件加工时,零件一次成形周期非常长,加工需一气呵成,这将是对保护气循环过滤系统极大的挑战。 [0005] When using this technique, especially for large processing complex metal member, a molding cycle is very long parts, coherent processing needs, it would be a great challenge for the protective gas filtration system.

发明内容 SUMMARY

[0006] 发明目的:针对上述现有存在的问题和不足,本发明的目的是提供3D打印金属粉末床成形腔体的保护气循环过滤装置及其优化方法,实现了高效、量化、可行、经济、安全、 能有效循环过滤加工烟尘,保证加工金属零件具有表面质量好,致密度高,机械性能好等特点。 [0006] Object of the invention: For the above-described conventional problems and disadvantages, an object of the present invention to provide a 3D print metallic protective gas circulating forming cavity the powder bed filtration apparatus and optimization method, to achieve an efficient, quantization, feasible and economical , safe, effective processing loop filter dust, ensure the machining metal parts with good surface quality, high density, good mechanical properties and other characteristics.

[0007] 技术方案:为了解决上述技术问题,本发明采用以下技术方案: [0007] Technical Solution: To solve the above problems, the present invention employs the following technical solution:

[0008] —种3D打印金属粉末床成形腔体的保护气循环过滤装置的优化方法,该保护气循环过滤装置包括进气分流口、吸气导流道、保护气循环防爆净化装置以及循环保护气电机装置,进气分流口、吸气导流道相对地设置于成形腔体中,且吸气导流道依次通过保护气循环防爆净化装置、循环保护气电机装置与进气分流口之间形成循环连通,进气分流口、吸气导流道中心的连线与成形腔体内腔的水平方向平行,通过调整加工烟尘竖直运动距离z,使得加工烟尘竖直运动距离z不大于吸气导流道的高度h,进而达到加工烟尘完全被吸气导流道捕获、成形腔体中进气分流口至吸气导流口的压力逐渐减小的目的;其中: [0008] - the protective gas circulating species 3D printing bed of metal powder forming a cavity filter optimization means, the protective gas circulating split filter means includes an intake port, an intake flow passage, the protective gas purifying device and a circulation loop explosion protection gas motor means, air diversion port, the intake flow channel is disposed opposite to the molding cavity, and the intake flow path passes through the protective gas circulating explosion purification device, the protective gas circulation between the motor means and the intake port split communication loop is formed, the intake port split, parallel to the horizontal direction and connecting the suction lumen of the flow channel forming cavity center, by adjusting the vertical movement distance z machining dust, soot processing such vertical movement distance z is not greater than the intake the height H of the flow channel, and then to process the captured soot completely the intake flow channel, forming a cavity in the intake port to the bypass flow port object suction pressure gradually decreases; and wherein:

[0009] z = v〇X l/vin-l/2XgX (l/vin)2 [0009] z = v〇X l / vin-l / 2XgX (l / vin) 2

[0010] 式中:I为进气分流口与吸气导流道的距离;VQ为加工烟尘脱离加工熔池表面竖直初速度;进气分流口中单个进气孔的保护气流速Vin = Qin/ (AX η),Qin为进气通道中的保护气体流量,A为进气分流口单个进气孔的截面面积;η为进气孔的数量。 [0010] where: I is split from the intake port and the intake flow path; early processing bath surface from the VQ vertical speed of soot processing; split intake mouth single intake hole protective gas flow rate Vin = Qin / (AX η), Qin is the flow rate of the protective gas into the intake passage, a is the cross-sectional area of ​​the intake port of a single split into the pores; [eta] is a number of inlet orifices.

[0011] 作为本发明的进一步优选,加工烟尘竖直运动距离ζ的调整是通过调节进气口流速Vin来实现的。 [0011] As a further preferred embodiment of the invention, the vertical movement distance of adjustment of machining dust ζ is achieved by adjusting the flow rate of the intake port Vin.

[0012] 作为本发明的进一步优选,进气口流速Vin的调节是通过配置进气分流口单个进气孔的截面面积A和进气孔的数量η来实现的。 [0012] As a further preferred embodiment of the invention, the flow rate of the intake port Vin is adjusted by configuring a single intake port split intake hole cross-sectional area A and the number of air intake η achieved.

[0013] 作为本发明的进一步优选,吸气导流道与保护气循环防爆净化装置之间的吸气通道上安装有第一电动阀开关;进气分流口与循环保护气电机装置之间的进气通道上安装有气体热流量监测控制器、压力表、第二电动阀开关;气体热流量监测控制器,用于将保护气进气分流口的气体流量信息反馈给循环保护气电机装置;压力表,用于将进气分流口的压力信息反馈给循环保护气电机装置;循环保护气电机装置根据所接收到的气体流量信息、 压力信息,通过控制第一电动阀开关、第二电动阀开关,自动调节保护气流量。 [0013] As a further preferred embodiment of the invention, the first motor is mounted on the intake valve opening and closing the intake passage between the flow channel and explosion protection gas circulating purification device; split between the intake port and the circulation of the protective gas motor means mounted gas heat flow monitoring controller, pressure gauge, a second electric switch valve intake passage; a gas flow monitoring thermal controller for the protective gas inlet port of the gas flow rate split feedback loop to the protective gas motor means; gauge, for the intake pressure information is fed back to the loop port bypass protective gas motor means; protective gas circulation motor means according to the received information to the gas flow rate, pressure information, by controlling the first electric switching valve, a second electric valve switch, automatically adjust the flow of shield gas.

[0014] 成形腔体配装有气压释放机构。 [0014] forming cavity fitted with pressure release means.

[0015] 作为本发明的进一步优选,所述气压释放机构包括与大气连通的电磁阀。 [0015] As a further preferred embodiment of the invention, the pressure release means comprises a solenoid valve communicating with the atmosphere.

[0016] 本发明的另一技术目的是提供一种3D打印金属粉末床成形腔体的保护气循环过滤装置,包括进气分流口、吸气导流道、保护气循环防爆净化装置以及循环保护气电机装置,进气分流口、吸气导流道相对地设置于成形腔体中,且吸气导流道依次通过保护气循环防爆净化装置、循环保护气电机装置与进气分流口之间形成循环连通,进气分流口、吸气导流道中心的连线与成形腔体内腔的水平方向平行,所述吸气导流道的高度h满足下列公式: [0016] Another technical object of the present invention is to provide a 3D print loop filter a shielding gas metal powder bed forming chamber, comprising an intake bypass port, the intake flow passage, the protective gas purifying device and a circulation loop explosion protection gas motor means, air diversion port, the intake flow channel is disposed opposite to the molding cavity, and the intake flow path passes through the protective gas circulating explosion purification device, the protective gas circulation between the motor means and the intake port split communication loop is formed, the intake port split, parallel to the horizontal direction and connecting the suction lumen of the flow channel forming cavity center, the intake flow channel height h satisfies the following formula:

Figure CN106513674BD00051

[0018] 其中,1为进气分流口与吸气导流道的距离;VQ为烟尘脱离加工熔池表面竖直初速度;A为进气分流口单个进气孔的截面面积;η为进气孔的数量;Qin为进气分流口的保护气体流量。 [0018] wherein 1 is split from the intake port and the intake flow path; as dust from the VQ First vertical speed processing bath surface; A is the cross-sectional area of ​​the intake port of a single split into the pores; [eta] is the feed the number of pores; Written by Qin split the intake port shielding gas flow.

[0019] 作为本发明的进一步优选,吸气导流道与保护气循环防爆净化装置之间的吸气通道上安装有第一电动阀开关;进气分流口与循环保护气电机装置之间的进气通道上安装有气体热流量监测控制器、压力表、第二电动阀开关;气体热流量监测控制器,用于将保护气进气分流口的气体流量信息反馈给循环保护气电机装置;压力表,用于将进气分流口的压力信息反馈给循环保护气电机装置;循环保护气电机装置根据所接收到的气体流量信息、 压力信息,通过控制第一电动阀开关、第二电动阀开关,自动调节保护气流量。 [0019] As a further preferred embodiment of the invention, the first motor is mounted on the intake valve opening and closing the intake passage between the flow channel and explosion protection gas circulating purification device; split between the intake port and the circulation of the protective gas motor means mounted gas heat flow monitoring controller, pressure gauge, a second electric switch valve intake passage; a gas flow monitoring thermal controller for the protective gas inlet port of the gas flow rate split feedback loop to the protective gas motor means; gauge, for the intake pressure information is fed back to the loop port bypass protective gas motor means; protective gas circulation motor means according to the received information to the gas flow rate, pressure information, by controlling the first electric switching valve, a second electric valve switch, automatically adjust the flow of shield gas.

[0020] 作为本发明的进一步优选,成形腔体配装有气压释放机构。 [0020] As a further preferred embodiment of the invention, the forming cavity is equipped with pressure release means.

[0021] 作为本发明的进一步优选,所述气压释放机构包括与大气连通的电磁阀。 [0021] As a further preferred embodiment of the invention, the pressure release means comprises a solenoid valve communicating with the atmosphere.

[0022] 有益效果:与现有技术相比,本发明具有以下优点: [0022] The beneficial effects: Compared with the prior art, the present invention has the following advantages:

[0023] (1)本发明在充分保证加工金属所需氧含量低于50ppm条件下,根据成形腔体进气口与出气口距离1及吸气口高度h,调节进气口流量Qin,考虑加工烟尘密度P和进气口截面面积A及数量n,建立w、h、Qin、P、A和η数学关系,保证加工烟尘能完全进入吸气口,达到烟尘除净和腔体压力平衡的要求。 [0023] (1) In the present invention, fully guarantee the desired metal oxide content of less than 50ppm processing conditions, according to the molding cavity 1 and the height h of the intake port and the intake port from the air outlet, the air inlet flow regulator Qin, consider processing smoke density P and the port cross-sectional area a and the number n, the establishment of w, h, Qin, P, a and η mathematical relationship, to ensure complete machining dust could enter the intake port, in addition to reach the smoke chamber and the net pressure balance Claim. 所优化成形腔体保护气循环过滤系统保证腔体成形基板洁净, 零件致密度达到100%,零件表面质量高并呈现金属光泽。 The optimization of the forming cavity protective gas filtration system to ensure clean the substrate forming the cavity, part of 100% density, high surface quality parts and exhibits a metallic luster.

[0024] (2)本发明能快速设计完成保护气循环过滤系统制造过程,大大降低以往设计及加工成本。 [0024] (2) The present invention is designed to quickly complete the shielding gas filtration system manufacturing process, greatly reducing the cost of conventional design and processing. 腔体烟尘能按成形腔压力梯度(由进气分流口至吸气导流口压力逐渐减小)方向运动,且完全进入吸气导流口,确保烟尘对加工金属构件零污染;成形腔体保持整洁,稳定可靠的保护气循环过滤系统为顺利制备加工周期长的复杂零件保驾护航。 Press molding cavity soot can cavity pressure gradient direction (from the intake port to bypass the intake port pressure flow decreases), and fully enters the suction port flow to ensure soot no pollution of the metal member workpiece; forming cavity kept clean, reliable shielding gas filtration system escort prepared long smooth machining cycle complex parts.

[0025] (3)本发明可将腔体循环气氧含量、杂质含量进行有效地降低控制,成形腔体气压差呈有序梯度变化,避免逆向负压引起的粉末倒吸现象,确保激光加工金属熔池、凝固件上方为循环滤净惰性气体,切实提高金属件加工质量。 [0025] (3) The present invention may be the oxygen content of the recycle gas the cavity, effectively reducing impurities control, the pressure difference between the forming cavity gradient was ordered to avoid suck powder reverse phenomenon caused by the negative pressure, to ensure that the laser processing of metal the bath, solidification of circular filter net member over an inert gas, and effectively improve the processing quality of the metal member.

[0026] ⑷本发明可维持液态熔池稳定性,避免加工过程熔滴飞溅现象;夹杂物的减少可显著提高熔体与已加工层/道润湿性,确保层/道间为优异全熔化/凝固冶金结合。 [0026] ⑷ the present invention can maintain stability of the bath liquid, the process to avoid the phenomenon of splashing droplet; reducing inclusions and can significantly increase the melt processed layer / channel wettability to ensure inter-layer / channel is excellent in the whole melt / solidification metallurgical bond. 熔体稳定无飞溅、良好润湿性及铺展性,为获得高表面质量和高致密试件提供了环境基础。 No splashing melt stable, good wettability and spreadability, the environment provides the foundation for high densification and high surface quality specimens.

[0027] (5)本发明进气通道流速可智能调控,因为:进气通道一侧分别设有气体热流量监测控制器,压力表,电动阀开关和循环保护气电机装置。 [0027] (5) the flow rate of the intake passage according to the present invention may be intelligent control, because: one side of the intake passage are respectively provided to monitor the gas flow controller thermal, pressure gauges, switches and electric valve motor protective gas circulation means. 进气分流口流速/流量信息反馈循环保护气电机装置,可迅速调节进气口流速,有效调控烟尘运动方向及流动速度。 Split vent flow rate of air / gas flow rate feedback loop motor protection apparatus can quickly adjust the flow rate of the intake port, effectively control the flow rate and direction of movement of dust.

[0028] (6)本发明可有效节约保护气使用量,能耗小,降低加工成本,无需频繁更换保护气瓶。 [0028] (6) The present invention can effectively save the amount of use of the protective gas, low energy consumption, reduce processing costs, without frequent replacement protect the cylinder.

[0029] (7)本发明可为腔体提高优异加工环境,激光能量能完全与所需加工粉末区域作用,避免成形过程中燃烧和爆炸等危险 [0029] (7) The present invention can improve the working environment is excellent in the cavity, the laser energy can be completely effect the desired powder processing region, avoiding forming during combustion and explosion hazard

附图说明 BRIEF DESCRIPTION

[0030] 图1是本发明粉末床腔体保护气循环过滤系统的结构示意图; [0030] FIG. 1 is a schematic view of the protective powder bed chamber air circulation filter system of the present invention;

[0031] 图2是本发明粉末床腔体保护气循环过滤系统的原理结构示意图; [0031] FIG. 2 is a schematic view of the principle of the present invention, the protective powder bed chamber air circulation filtration system;

[0032] 图3 (a)是本发明粉末床腔体保护气循环过滤系统改进前的保护气流场矢量图; [0032] FIG. 3 (a) is a powder bed of the present invention, the cavity before the protective gas flow field protecting gas filtration system improved vector;

[0033] 图3⑹是本发明粉末床腔体保护气循环过滤系统改进后的保护气流场矢量图; [0033] FIG 3⑹ protective gas flow field vector is the protection of the powder bed chamber air circulation system of the present invention improves filtration;

[0034] 图4 (a)是本发明粉末床腔体保护气循环过滤系统改进前的保护气压分布图; [0034] FIG. 4 (a) is a front profile view of a protective powder bed pressure chamber protective gas circulation system of the present invention improves filtration;

[0035] 图4⑹是本发明粉末床腔体保护气循环过滤系统改进后的保护气压分布图; [0035] FIG 4⑹ profile is protected after the powder bed pressure chamber protective gas circulation system of the present invention improves filtration;

[0036] 图5是本发明粉末床腔体保护气循环过滤系统改进前进气分流口粉末堆积图; [0036] FIG 5 is a powder bed of the present invention a cavity protection improved air filtration system proceeds FIG Aerated bulk powder port;

[0037] 图6是本发明粉末床腔体保护气循环过滤系统改进后进气分流口粉末堆积图。 [0037] FIG. 6 is a protective powder bed chamber air circulation system of the present invention improves filtration split rear air outlet powder bulk FIG.

具体实施方式 detailed description

[0038] 下面结合附图和具体实施例,进一步阐明本发明,应理解这些实施例仅用于说明本发明而不用于限制本发明的范围,在阅读了本发明之后,本领域技术人员对本发明的各种等价形式的修改均落于本申请所附权利要求所限定的范围。 [0038] conjunction with the accompanying drawings and the following specific examples further illustrate the invention, it should be understood that these embodiments are illustrative only and the present invention is not intended to limit the scope of the present invention, after reading this disclosure, those skilled in the art of the present invention various modifications are equivalents fall within the present application as defined in the appended claims scope.

[0039] 如图1〜6所示,本发明的3D打印金属粉末床成形腔体的保护气循环过滤装置,包括保护气循环过滤净化机构,以及设在成形腔体内的进气分流口和吸气导流道,其中:所述进气分流口包含多个进气孔;所述吸气导流道为为台阶式导流道,且开口设在侧面;所述保护气循环过滤净化机构,包括通过管道依次连接气体热流量监测控制器、压力表、第一电动阀开关、循环保护气电机装置、气体循环防爆机构和第二电动阀开关,所述气体热流量监测控制器通过管道与进气分流口连通,所述第二电动阀开关通过管道与吸气导流道连通,从而使保护气循环过滤净化机构与成形腔体形成循环连通。 [0039] As shown, the protective gas circulating 3D printing metal powder bed according to the present invention, the forming cavity 1~6 filter apparatus comprising a loop filter protective gas purification unit and the molding cavity provided in the intake port and the suction split gas flow passage, wherein: the intake port comprises a plurality of split intake hole; the flow path for the intake flow channel is stepped and an opening provided on a side; the loop filter protective gas purification unit comprising sequentially connecting the hot gas flow through line monitoring controller, pressure gauge, a first motor valve switch, the motor protective gas circulating means, gas circulating anti-explosion mechanism and a second motor valve switch, the hot gas flow through the conduit and into the monitoring controller Aerated communication port, said second motor valve switch in communication with the intake flow path through the conduit so that the protective gas circulating filter purification and means forming cavity is formed in communication cycle.

[0040] 本发明对3D打印金属粉末床成形腔体保护气循环过滤系统的改进原理依据:根据粉末床成形腔体尺寸(长L、宽W和高Η),设计并确定腔体内保护气进气分流口与吸气导流道距离1,吸气导流道高度为h。 [0040] The 3D printing metal powder bed forming cavity protective gas circulation filtering system principles according to the invention: (length L, width W and height [eta]) The powder bed forming cavity size, design, and determine the cavity protective gas feed Aerated flow path from the intake port 1, the intake flow channel height to h. 通常,W与1为相互平行关系,加工金属烟尘密度Ρ,单进气孔截面面积A,进气口数量为η,进气通道保护气流量Qin。 Typically, W 1 and parallel relationship to each other, the processing of metal dust density [rho], a single cross-sectional area of ​​the intake port A, [eta] is the number of the intake port, the intake air flow path protection Qin. 因此,进气口流速Vin=Qiry(AXη)。 Thus, the flow rate of intake port Vin = Qiry (AXη). 加工过程中,离吸气导流道距离最远的烟尘最容易逃逸并最终成为杂质气体而污染加工金属表面,其最大距离为1;烟尘脱离加工熔池表面其水平速度迅速升至νιη并随后匀速运动,烟尘至吸气导流道时间t = l/vin;烟尘脱离加工熔池表面竖直初速度为v〇,随后在烟尘重力作用下,作加速度为g的勾减速运动,在t时间范围内运动距离为z = VQ X l/Vin-1/2 X g X (1/vin )2。 Processing, from the intake flow channel farthest most easily released soot and eventually contaminate the impurity gas processing metal surface, which is a maximum distance of 1; dust from the bath surface horizontal machining speed and then quickly raised to νιη uniform motion, smoke to the intake flow channel time t = l / vin; early processing dust from the bath surface as v〇 vertical speed, then the smoke gravity acceleration g as hook deceleration, at time t a movement distance of the range of z = VQ X l / Vin-1/2 X g X (1 / vin) 2. 加工烟尘竖直运动距离Z应不大于h,即Ζ〇Ί,ν〇Χ l/vin_l/2XgX (1/vin) 2<h,以保证烟尘完全被吸气导流道捕获,进而保证加工金属样件具有表面质量好,致密度高,机械性能好等特点。 Vertical movement soot processing should not exceed the distance Z, h, the Ζ〇Ί, ν〇Χ l / vin_l / 2XgX (1 / vin) 2 <h, to ensure complete dust suction flow channel are trapped, thus ensuring metal machining sample having good surface quality, high density, good mechanical properties and other characteristics.

[0041] 以下通过实施例具体说明本发明的技术方案: [0041] The following detailed description of the technical solution of the present invention by way of example:

[0042]优化前 [0042] optimization ago

[0043] 根据粉末床成形腔体:长L = 700mm、宽W = 450mm和高H= 250mm,设计并确定腔体内保护气进气分流口29与吸气导流道27距离1 = 200mm,吸气导流道高度为h = 30mm。 [0043] The powder bed forming cavity: length L = 700mm, width W = 450mm high and H = 250mm, and designed to determine the protective gas chamber inlet ports 27 1 = 200mm split from the intake flow path 29, the suction the air flow passage to the height h = 30mm. 通常,W与1为相互平行关系,加工金属为铝合金粉末。 Typically, W and in parallel relation to each other is 1, the processing metal is an aluminum alloy powder. 通常,激光与铝粉相互作用后形成的熔池,其温度高于1300°C,故所形成烟尘Ct-Al2O3密度P = 3.9g/cm3,单进气孔圆截面面积A= 12.56mm2, 进气口数量为η = 16,进气通道21保护气流量Qin = 40L/min。 Typically, the molten pool formed after laser interaction with aluminum, a temperature above 1300 ° C, so that the smoke density Ct-Al2O3 P = 3.9g / cm3 is formed into a single circular hole cross-sectional area A = 12.56mm2, into port number is η = 16, the intake passage 21 protects the gas flow rate Qin = 40L / min. 因此,进气口流速Vin = Qin/ (AX η) = 3 · 3m/s 〇 Thus, the flow rate of intake port Vin = Qin / (AX η) = 3 · 3m / s billion

[0044] 加工过程中,离吸气导流道27距离最远的烟尘最容易逃逸并最终成为杂质气体而污染加工金属表面,其最大距离为l = 200mm;烟尘脱离加工熔池表面其水平速度迅速升至Vin并随后匀速运动,烟尘至吸气导流道27时间t = Vvin,本实施例中,t为0.06s。 [0044] processing, from the intake flow path 27 from the furthest most likely to escape the soot and eventually contaminate the impurity gas processing metal surface, which is the maximum distance l = 200mm; dust from the processing bath surface horizontal velocity Vin and then quickly raised to uniform motion, smoke flow channel 27 to the suction time t = Vvin, in this embodiment, t is 0.06s.

[0045] 烟尘脱离加工熔池表面竖直初速度为vo。 [0045] First processing bath surface from dust vertical velocity vo. 通常,激光加工铝合金粉体所形成熔池表面为外对流,即熔池中心熔体速度竖直向上。 Typically, the laser processing of the aluminum powder is formed into an outer bath surface convection, i.e. the central melt puddle velocity vertically upward. 在本实例实施过程中,数值模拟研究方法确定恪池中心恪体竖直速度为lm/s,故初速度VQ定位lm/s。 In the process of the present embodiment example, the numerical simulation method for determining cell center Verified Verified body vertical speed of lm / s, so the initial velocity VQ positioned lm / s.

[0046] 随后在烟尘重力作用下,作加速度为9.8m/s2的匀减速运动,烟尘初始速度为V0 = lm/s,当速度减至Om/s所需时间为0. Is。 [0046] In the subsequent soot gravity as acceleration 9.8m / s2 the uniform deceleration, the soot initial velocity V0 = lm / s, when the speed is reduced to Om / s Time required to 0. Is. 烟尘运动形式为:t = 0〜0.06s。 Movement soot form: t = 0~0.06s. 烟尘在成形腔保护气循环过滤系统优化前加工烟尘竖直运动距离Z = VqX l/vin-l/2XgX (1/Vin)2为42mm; Soot forming cavity protective gas before recycling system optimization processing soot from the vertical movement of 42mm 2 Z = VqX l / vin-l / 2XgX (1 / Vin);

[0047] 3D打印Al合金金属粉末,其工艺参数为:激光功率P为200W,扫描速度V为1200mm/ s,扫描间距η为50μηι,铺粉厚度k为30μηι。 [0047] 3D printing an Al alloy metal powders, the process parameters were: laser power P is 200W, the scanning speed V is 1200mm / s, η is the scanning pitch 50μηι, dusting thickness k of 30μηι.

[0048]优化后 [0048] After optimization

[0049] 根据粉末床成形腔体:长L = 700mm、宽W = 450mm和高H= 250mm,设计并确定腔体内保护气进气分流口29与吸气导流道27距离1 = 200mm,吸气导流道高度为h = 30mm。 [0049] The powder bed forming cavity: length L = 700mm, width W = 450mm high and H = 250mm, and designed to determine the protective gas chamber inlet ports 27 1 = 200mm split from the intake flow path 29, the suction the air flow passage to the height h = 30mm. 通常,W与1为相互平行关系,加工金属为铝合金粉末。 Typically, W and in parallel relation to each other is 1, the processing metal is an aluminum alloy powder. 通常,激光与铝粉相互作用后形成的熔池,其温度高于1300°C,故所形成烟尘Ct-Al2O3密度P = 3.9g/cm3,单进气孔圆截面面积A = 28.26mm2, 进气口数量为η = 20,进气通道21保护气流量Qin = 40L/min。 Typically, the molten pool formed after laser interaction with aluminum, a temperature above 1300 ° C, so that the smoke density Ct-Al2O3 P = 3.9g / cm3 is formed into a single circular hole cross-sectional area A = 28.26mm2, into port number is η = 20, the intake passage 21 protects the gas flow rate Qin = 40L / min. 因此,进气口流速Vin = Qiry(AX n) = 1 · 2m/s 〇 Thus, the flow rate of intake port Vin = Qiry (AX n) = 1 · 2m / s billion

[0050] 加工过程中,离吸气导流道27距离最远的烟尘最容易逃逸并最终成为杂质气体而污染加工金属表面,其最大距离为l = 200mm;烟尘脱离加工熔池表面其水平速度迅速升至Vin并随后匀速运动,烟尘至吸气导流道27时间t = l/vin,本实施例中,t为0.17s。 [0050] processing, from the intake flow path 27 from the furthest most likely to escape the soot and eventually contaminate the impurity gas processing metal surface, which is the maximum distance l = 200mm; dust from the processing bath surface horizontal velocity Vin and then quickly raised to uniform motion, smoke flow channel 27 to the suction time t = l / vin, in this embodiment, t is 0.17s.

[0051] 烟尘脱离加工熔池表面竖直初速度为vo。 [0051] First processing bath surface from dust vertical velocity vo. 通常,激光加工铝合金粉体所形成熔池表面为外对流,即熔池中心熔体速度竖直向上。 Typically, the laser processing of the aluminum powder is formed into an outer bath surface convection, i.e. the central melt puddle velocity vertically upward. 在本实例实施过程中,数值模拟研究方法确定恪池中心恪体竖直速度为lm/s,故初速度VQ定位lm/s。 In the process of the present embodiment example, the numerical simulation method for determining cell center Verified Verified body vertical speed of lm / s, so the initial velocity VQ positioned lm / s.

[0052] 随后在烟尘重力作用下,作加速度为9.8m/s2的匀减速运动,烟尘初始速度为V0 = lm/s,当速度减至Om/s所需时间为0. Is。 [0052] In the subsequent soot gravity as acceleration 9.8m / s2 the uniform deceleration, the soot initial velocity V0 = lm / s, when the speed is reduced to Om / s Time required to 0. Is. 烟尘运动形式分为两段:ti = 0〜0. Is,t2 = 0.1〜 0.17s;烟尘在成形腔保护气循环过滤系统中的加工烟尘竖直运动距离z = vo X 1/νιη-1/2 X gX (l/vin)2为27mm; Soot movement form is divided into two sections: ti = 0~0 Is, t2 = 0.1~ 0.17s; smoke dust vertical motion processing chamber forming the protective gas circulating filter system from z = vo X 1 / νιη-1 /. 2 X gX (l / vin) 2 to 27mm;

[0053] 3D打印Al合金金属粉末,其工艺参数为:激光功率P为200W,扫描速度V为1200mm/ s,扫描间距η为50μηι,铺粉厚度k为30μηι。 [0053] 3D printing an Al alloy metal powders, the process parameters were: laser power P is 200W, the scanning speed V is 1200mm / s, η is the scanning pitch 50μηι, dusting thickness k of 30μηι.

[0054] 加工烟尘竖直运动距离ζ应不大于h,即ζSh,据以上结果可知: [0054] The vertical movement of soot processing should not exceed the distance ζ h, i.e. ζSh, according to the results described above:

[0055] 优化前:h = 42mm> 30mm; Before [0055] Optimization: h = 42mm> 30mm;

[0056] 优化后:h = 27mm〈30mm。 After [0056] Optimization: h = 27mm <30mm.

[0057] 故可得出,优化后所设计的保护气循环过滤装置可保证烟尘完全被吸气导流道捕获,进而保证加工金属样件具有表面质量好,致密度高,机械性能好等特点。 [0057] it can be concluded that the optimized design of protective gas ensures circulation filtering apparatus is completely captured dust suction flow path, thereby ensuring the sample processing metal having a good surface quality, high density, good mechanical properties and other characteristics .

[0058] 进一步改进,经过上述设计加工腔体压强分布在进气分流口29与吸气导流道27距离1上为梯度减小变化状态。 [0058] Further improvements, design and processing through said cavity air pressure distribution in the split state with the intake port 29 to reduce the flow channel 27 on a gradient of the distance change. 避免在进气口侧产生负压而导致加工烟尘堆积,造成不必要的设备机械故障,优化前后压力分布如图4所示。 To avoid a negative pressure in the intake port side of the soot accumulation processing result, unnecessary mechanical failure of the device, before and after optimization pressure distribution as shown in FIG. 优化前后加工过程烟尘运动图5和图6。 Motion smoke before and after optimization process in Figures 5 and 6.

[0059] 当加工腔体压力达到危险阙值时,压力释放电磁阀31将自动与大气接通,完成气压释放,以此来保证设备安全性,实现加工腔体内外压力平衡。 [0059] When the processing chamber pressure reaches a dangerous threshold, a pressure release solenoid valve 31 is turned on automatically with the atmosphere, the pressure releasing is completed, in order to ensure the security of equipment, and external pressure equalization processing chamber.

Claims (10)

  1. 1. 一种3D打印金属粉末床成形腔体的保护气循环过滤装置的优化方法,该保护气循环过滤装置包括进气分流口、吸气导流道、保护气循环防爆净化装置以及循环保护气电机装置,进气分流口、吸气导流道相对地设置于成形腔体中,且吸气导流道依次通过保护气循环防爆净化装置、循环保护气电机装置与进气分流口之间形成循环连通,进气分流口、吸气导流道中心的连线与成形腔体内腔的水平方向平行,其特征在于,通过调整加工烟尘竖直运动距离z,单位为mm,使得加工烟尘竖直运动距离z不大于吸气导流道的高度h,单位为mm, 进而达到加工烟尘完全被吸气导流道捕获、成形腔体中进气分流口至吸气导流口的压力逐渐减小的目的;其中: 1. A method of optimizing apparatus 3D print protective gas circulating bed of metal powder forming a cavity filter, the protective gas circulating split filter means includes an intake port, an intake flow passage, the protective gas circulation loop and explosion protection gas purification apparatus motor means, the intake bypass port, the intake flow channel is disposed opposite to the molding cavity, and the intake flow path passes through the protective gas circulating explosion purification device, the protective gas circulation is formed between the motor means and the intake port split communication cycle, the intake port split, parallel to the horizontal direction connecting the cavity forming chamber intake flow track center, characterized in that, by adjusting the vertical movement distance Z soot processing, in units of mm, so that the vertical smoke processing movement distance z is not greater than the height h of the intake flow channel, in units of mm, so as to achieve complete processing of the captured dust intake flow channel, forming a cavity in the intake port to bypass the intake port pressure gradually decreases guide purpose; wherein:
    Figure CN106513674BC00021
    式中:1为进气分流口与吸气导流道的距离,单位为mm;V〇为加工烟尘脱离加工熔池表面竖直初速度,单位为m/s;进气分流口中单个进气孔的保护气流速Vin = Qin/(AXn),单位为m/s; Qin为进气通道中的保护气体流量,单位为L/min; A为进气分流口单个进气孔的截面面积,单位为mm2; η为进气孔的数量。 Wherein: 1 is split from the intake port and the intake flow channel, in units of mm; V〇 departing early processing bath surface speed of the vertical soot processing units of m / s; split intake mouth single intake protective gas flow holes Vin = Qin / (AXn), in units of m / s; Qin protective gas flow in the intake passage, in units of L / min; a is the cross-sectional area of ​​the intake port of a single split into the pores, units mm2; η is a number of inlet orifices.
  2. 2. 根据权利要求1所述3D打印金属粉末床成形腔体的保护气循环过滤装置的优化方法,其特征在于,加工烟尘竖直运动距离ζ的调整是通过调节进气口流速Vln来实现的。 The 3D printing a metal powder to the bed forming the protective gas circulating claim cavity filter optimization means, characterized in that the vertical moving distance of the machining dust ζ adjustment is achieved by adjusting the flow rate of the intake port Vln .
  3. 3. 根据权利要求2所述3D打印金属粉末床成形腔体的保护气循环过滤装置的优化方法,其特征在于,进气口流速νιη的调节是通过配置进气分流口单个进气孔的截面面积A和进气孔的数量η来实现的。 Cross-section according to claim 2 of the protective gas circulating 3D printing metal powder bed forming cavity of the filter device requires optimization method, wherein the flow rate adjusting νιη intake port is disposed through the intake port of the intake port split single a inlet port area and the number η achieved.
  4. 4. 根据权利要求1所述3D打印金属粉末床成形腔体的保护气循环过滤装置的优化方法,其特征在于,吸气导流道与保护气循环防爆净化装置之间的吸气通道上安装有第一电动阀开关; 进气分流口与循环保护气电机装置之间的进气通道上安装有气体热流量监测控制器、 压力表、第二电动阀开关; 气体热流量监测控制器,用于将保护气进气分流口的气体流量信息反馈给循环保护气电机装置; 压力表,用于将进气分流口的压力信息反馈给循环保护气电机装置; 循环保护气电机装置根据所接收到的气体流量信息、压力信息,通过控制第一电动阀开关、第二电动阀开关,自动调节保护气流量。 1 according to the 3D Printing protective gas circulating bed of metal powder forming cavity optimization method of claim filtration apparatus, characterized in that, mounted on the suction passage between the suction flow path and the protective gas circulating purification device Explosion a first electric switching valve; the heat flow monitor attached to a gas controller, a pressure gauge, a second electric switch valve of the intake passage between the intake port and the split protective gas circulation motor means; hot gas flow monitoring controller, with the protective gas flow in the gas feed information back to the gas circulation port split protective gas motor means; gauge, air pressure information for feedback to a cyclic split vent protective gas motor means; protective gas circulating apparatus in accordance with the received motor gas flow rate information, pressure information, by controlling the first electric switching valve, the second motor valve switch, automatically adjust the flow of shield gas.
  5. 5. 根据权利要求1所述3D打印金属粉末床成形腔体的保护气循环过滤装置的优化方法,其特征在于,成形腔体配装有气压释放机构。 5.1 The protective gas circulating 3D printing metal powder bed forming cavity optimization method according to claim filtration device, characterized in that the molding cavity fitted with a pressure release mechanism.
  6. 6. 根据权利要求5所述3D打印金属粉末床成形腔体的保护气循环过滤装置的优化方法,其特征在于,所述气压释放机构包括与大气连通的电磁阀。 6.5 The protective gas circulating 3D printing metal powder bed forming cavity optimization method according to claim filtration device, wherein said pressure releasing means comprises a solenoid valve communicating with the atmosphere.
  7. 7. —种采用权利要求1所述的优化方法的3D打印金属粉末床成形腔体的保护气循环过滤装置,包括进气分流口、吸气导流道、保护气循环防爆净化装置以及循环保护气电机装置,进气分流口、吸气导流道相对地设置于成形腔体中,且吸气导流道依次通过保护气循环防爆净化装置、循环保护气电机装置与进气分流口之间形成循环连通,进气分流口、吸气导流道中心的连线与成形腔体内腔的水平方向平行,其特征在于,所述吸气导流道的高度h满足下列公式: 7. - kind of shielding gas circulation filtering apparatus using 3D printing metal powder bed forming cavity optimization method according to claim 1, comprising an intake bypass port, the intake flow passage, the protective gas purifying device and a circulation loop explosion protection gas motor means, air diversion port, the intake flow channel is disposed opposite to the molding cavity, and the intake flow path passes through the protective gas circulating explosion purification device, the protective gas circulation between the motor means and the intake port split communication loop is formed, the intake port split, parallel connection with the forming cavity chamber horizontal center intake flow channel, wherein said suction flow channel height h satisfies the following equation:
    Figure CN106513674BC00031
    其中,1为进气分流口与吸气导流道的距离,单位为mm;VQ为烟尘脱离加工熔池表面竖直初速度,单位为m/s; A为进气分流口单个进气孔的截面面积,单位为mm2; η为进气孔的数量; Qin为进气分流口的保护气体流量,单位为L/min。 Wherein 1 is split from the intake port and the intake flow channel, in units of mm; VQ First of dust from the surface of the bath vertical speed processing, in units of m / s; A is a single split vent air intake hole cross-sectional area, in units of mm2; η is a number of inlet orifices; Written by Qin split the intake port shielding gas flow, in units of L / min.
  8. 8. 根据权利要求7所述3D打印金属粉末床成形腔体的保护气循环过滤装置,其特征在于,吸气导流道与保护气循环防爆净化装置之间的吸气通道上安装有第一电动阀开关; 进气分流口与循环保护气电机装置之间的进气通道上安装有气体热流量监测控制器、 压力表、第二电动阀开关; 气体热流量监测控制器,用于将保护气进气分流口的气体流量信息反馈给循环保护气电机装置; 压力表,用于将进气分流口的压力信息反馈给循环保护气电机装置; 循环保护气电机装置根据所接收到的气体流量信息、压力信息,通过控制第一电动阀开关、第二电动阀开关,自动调节保护气流量。 8.7 The protective gas circulating 3D printing metal powder bed filter means forming cavity according to claim, characterized in that, mounted on the first intake passage between the suction flow path and the protective gas circulating purification device Explosion electric switching valve; the heat flow monitor attached to a gas controller, pressure gauge intake passage between the intake port and the shunt protection cycle gas motor means, a second electric switching valve; hot gas flow controllers monitoring, for protection an intake air flow rate of the gas bypass port information is fed back to the motor protective gas circulation means; gauge, air pressure information for the split vent gas is fed back to the motor protection apparatus cyclic; circulating gas flow shielding gas motor means according to the received information, pressure information, by controlling the first electric switching valve, the second motor valve switch, automatically adjust the flow of shield gas.
  9. 9. 根据权利要求7所述3D打印金属粉末床成形腔体的保护气循环过滤装置,其特征在于,成形腔体配装有气压释放机构。 According to claim 7 of the protective gas circulating 3D printing metal powder bed forming cavity filter device, characterized in that the molding cavity fitted with a pressure release mechanism.
  10. 10. 根据权利要求9所述3D打印金属粉末床成形腔体的保护气循环过滤装置,其特征在于,所述气压释放机构包括与大气连通的电磁阀。 10.9 the protective gas circulating 3D printing metal powder bed forming cavity filter device according to claim, characterized in that the pressure releasing mechanism includes a solenoid valve communicating with the atmosphere.
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