CN111663057A - 一种激光3d打印碳化硅陶铝复合材料及其制备方法 - Google Patents

一种激光3d打印碳化硅陶铝复合材料及其制备方法 Download PDF

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CN111663057A
CN111663057A CN201910170802.XA CN201910170802A CN111663057A CN 111663057 A CN111663057 A CN 111663057A CN 201910170802 A CN201910170802 A CN 201910170802A CN 111663057 A CN111663057 A CN 111663057A
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陈照峰
廖家豪
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Abstract

本发明公开了一种激光3D打印碳化硅陶铝复合材料,由碳化硅颗粒、粘结剂、铝合金基体组成,其中碳化硅颗粒体积分数为50~75%,粘结剂体积分数为3~10%,铝合金基体体积分数为15~47%;其特征在于碳化硅颗粒和粘结剂通过激光3D打印成碳化硅多孔陶瓷预制体,铝合金填充在碳化硅多孔陶瓷预制体中;所述的碳化硅颗粒粒径为10~50μm;所述的粘结剂为铝粉,铝粉粒径为5~40μm。本发明采用选区激光烧结3D打印技术制备陶瓷多孔预制体,不仅解决了传统制备方法工艺流程长、工序复杂、成本高等问题,还能使材料内部组织结构均匀,材料尺寸精度更高,显著提高了其结构稳定性和性能可靠性。

Description

一种激光3D打印碳化硅陶铝复合材料及其制备方法
技术领域
本发明涉及一种碳化硅陶铝复合材料及其制备方法,特别涉及一种激光3D打印碳化硅陶铝复合材料及其制备方法。
背景技术
颗粒增强铝基复合材料因具有比模量大、比强度高、热膨胀系数低、高导热、导电、耐磨以及耐疲劳性能好等特点,近年来已经被广泛应用于航空航天、高铁、精密仪器、电子封装等领域。颗粒增强铝基复合材料的性能很大程度上取决于其制备工艺和方法,目前铝基复合材料的制备方法主要有粉末冶金法、搅拌铸造法、熔融体浸渗法等,但是这些方法制备的铝基复合材料存在致密度不高、内部缺陷较多、材料组织成分不均匀、制备周期长、尺寸形状受限等缺点,从而限制了铝基复合材料的应用范围和深度。
3D打印技术又称增材制造技术,是一种结合计算机、材料、机械等多领域的系统性、综合性的技术,3D打印技术与传统的制造技术相比,具有如下特点:①节约原材料,能够实现“近净成形”;②降低设备成本;③可以制造形状复杂、难加工材料;④设计生产空间灵活可控;⑤缩短了生产时间;⑥可以用于零件修复;⑦可以结合铸造技术,进行复合成形,即在铸件上直接打印难铸造结构或零部件,因此,可采用增材制造技术制备传统工艺方法难以加工的构件。
申请公布号为CN107586136A的中国发明专利公开了一种3D打印氮化硅陶瓷的方法,该发明采用3D打印技术,不仅可以制备复杂形状的氮化硅陶瓷零件,并且利用打印过程中的双层刮刀成型技术,可使β相氮化硅取向排布,经脱脂-烧结后,可获得具有复杂形状的织构化氮化硅陶瓷。所制备的氮化硅零件具有优异的可靠性、力学性能、热学性能、耐磨性等。
申请公布号为CN108129168A的中国发明专利公开了一种基于3D打印的铝基复合材料的制备方法及铝基复合材料。此铝基复合材料通过3D打印制备陶瓷多孔体毛坯、陶瓷多孔体毛坯的固化与烧结以及压力浸渗制备铝基复合材料制得;首先,采用3D打印技术成形铝基复合材料用陶瓷多孔体毛坯;然后,将其在二氧化碳气氛或空气气氛中固化;继而,在空气炉中进行一体化的脱脂-烧结处理,制得铝基复合材料用陶瓷多孔体;最后,采用压力浸渗法制备铝基复合材料。
申请公布号为CN108504888A的中国发明专利公开了一种陶瓷复合球增强金属基复合材料的制备方法,属于金属基复合材料领域。将金属粉、水玻璃、聚乳酸、环氧树脂、水配成的3D打印用的浆料,浆料中固体含量为60%~75%,将配好的浆料倒入料斗中,通过3D打印机打印出单层基体板,所述单层基体板的上下表面均设有半球孔或者只有一个表面设有半球孔,单层基体板的厚度为6~15mm,半球孔的直径3~5mm,球间距3~5mm;在单层基体板的半球孔中添加陶瓷混合浆料,然后将多个单层基体板叠加,进行热压烧结后得到陶瓷复合球增强的金属基复合材料。
综上所述,目前3D打印陶瓷和金属复合材料主要是通过将陶瓷粉体或者金属粉体配制成浆料,再通过3D打印技术打印出陶瓷或者金属坯体,其虽然发挥了3D打印技术节省制备周期、降低制备成本等优点,但是浆料3D打印制备出来的材料较为粗糙,材料内部烧结不完全,易残留制备缺陷,且制品尺寸精度较差。
发明内容
为解决上述问题,本发明提出一种激光3D打印碳化硅陶铝复合材料及其制备方法,既充分发挥了3D打印技术在铝基复合材料制备方面的优势,又改善了3D打印铝基复合材料内部组织结构,使其性能可靠性显著提高。
一种激光3D打印碳化硅陶铝复合材料,由碳化硅颗粒、粘结剂、铝合金基体组成,其中碳化硅颗粒体积分数为50~75%,粘结剂体积分数为3~10%,铝合金基体体积分数为15~47%;其特征在于碳化硅颗粒和粘结剂通过激光3D打印成碳化硅多孔陶瓷预制体,铝合金填充在碳化硅多孔陶瓷预制体中;所述的碳化硅颗粒粒径为10~50μm;所述的粘结剂为铝粉,铝粉粒径为5~40μm;一种激光3D打印碳化硅陶铝复合材料的制备方法,其特征在于包括下述顺序的步骤:
(1)将碳化硅颗粒和粘结剂混合均匀,放入激光3D打印粉床中,采用选区激光烧结技术激光3D打印碳化硅陶瓷多孔预制体;
(2)将激光3D打印好的碳化硅陶瓷多孔预制体放入高温烧结炉中进行高温烧结,烧结气氛为真空或者氩气,烧结温度为800~1500℃,得到碳化硅多孔陶瓷体;
(3)将制备好的碳化硅多孔陶瓷体表面进行数控机加工,用无水乙醇超声清洗后烘干,然后放入石墨模具中进行工装;
(4)将步骤(3)中的工装放入真空气压浸渗炉中,抽真空至0.1~50Pa,升温至500~800℃,将熔融的铝合金浇注到工装内,加注气压至0.5~5.0MPa,完成铝合金的真空压力浸渗,得到制备好的激光3D打印碳化硅陶铝复合材料。
本发明有益效果:(1)采用选区激光烧结3D打印技术制备陶瓷多孔预制体,不仅解决了传统制备方法工艺流程长、工序复杂、成本高等问题,还能使材料内部组织结构均匀,材料尺寸精度更高;(2)采用铝粉作为粘结剂,可以不引入新的杂质元素,使碳化硅多孔陶瓷体结构更加均匀稳定;(3)采用真空气压浸渗铝合金,可以有效排除多孔陶瓷体内的气体,避免在材料内部形成孔隙缺陷,有效提高铝基复合材料的综合性能。
附图说明
下面结合附图和实施例对本发明作进一步说明。
图1是本发明的实施例中制得的激光3D打印碳化硅陶铝复合材料的压缩强度应力-位移曲线图;
图2是本发明的实施例中制得的激光3D打印碳化硅陶铝复合材料的弯曲强度应力-位移曲线图。
具体实施方式
下面结合具体实施例,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。
实施例
一种激光3D打印碳化硅陶铝复合材料,由碳化硅颗粒、粘结剂、铝合金基体组成,其中碳化硅颗粒体积分数为60%,粘结剂体积分数为5%,铝合金基体体积分数为35%;其特征在于碳化硅颗粒和粘结剂通过激光3D打印成碳化硅多孔陶瓷预制体,铝合金填充在碳化硅多孔陶瓷预制体中;所述的碳化硅颗粒粒径为25μm;所述的粘结剂为铝粉,铝粉粒径为20μm;一种激光3D打印碳化硅陶铝复合材料的制备方法,其特征在于包括下述顺序的步骤:
(1)将碳化硅颗粒和粘结剂混合均匀,放入激光3D打印粉床中,采用选区激光烧结技术激光3D打印碳化硅陶瓷多孔预制体;
(2)将激光3D打印好的碳化硅陶瓷多孔预制体放入高温烧结炉中进行高温烧结,烧结气氛为真空或者氩气,烧结温度为1200℃,得到碳化硅多孔陶瓷体;
(3)将制备好的碳化硅多孔陶瓷体表面进行数控机加工,用无水乙醇超声清洗后烘干,然后放入石墨模具中进行工装;
(4)将步骤(3)中的工装放入真空气压浸渗炉中,抽真空至1.0Pa,升温至600℃,将熔融的铝合金浇注到工装内,加注气压至2.0MPa,完成铝合金的真空压力浸渗,得到制备好的激光3D打印碳化硅陶铝复合材料。
采用本实施例的制备方法制成的激光3D打印碳化硅陶铝复合材料压缩强度达到400MPa左右,弯曲强度达到390MPa左右;图1中展示了激光3D打印碳化硅陶铝复合材料压缩强度应力-位移曲线,图2中展示了激光3D打印碳化硅陶铝复合材料弯曲强度应力-位移曲线。
上述仅为本发明的具体实施方式,但本发明的设计构思并不局限于此,凡利用此构思对本发明进行非实质性的改动,均应属于侵犯本发明保护的范围的行为。但凡是未脱离本发明技术方案的内容,依据本发明的技术实质对以上实施例所作的任何形式的简单修改、等同变化与改型,仍属于本发明技术方案的保护范围。

Claims (1)

1.一种激光3D打印碳化硅陶铝复合材料,由碳化硅颗粒、粘结剂、铝合金基体组成,其中碳化硅颗粒体积分数为50~75%,粘结剂体积分数为3~10%,铝合金基体体积分数为15~47%;其特征在于碳化硅颗粒和粘结剂通过激光3D打印成碳化硅多孔陶瓷预制体,铝合金填充在碳化硅多孔陶瓷预制体中;所述的碳化硅颗粒粒径为10~50μm;所述的粘结剂为铝粉,铝粉粒径为5~40μm;一种激光3D打印碳化硅陶铝复合材料的制备方法,其特征在于包括下述顺序的步骤:
(1)将碳化硅颗粒和粘结剂混合均匀,放入激光3D打印粉床中,采用选区激光烧结技术激光3D打印碳化硅陶瓷多孔预制体;
(2)将激光3D打印好的碳化硅陶瓷多孔预制体放入高温烧结炉中进行高温烧结,烧结气氛为真空或者氩气,烧结温度为800~1500℃,得到碳化硅多孔陶瓷体;
(3)将制备好的碳化硅多孔陶瓷体表面进行数控机加工,用无水乙醇超声清洗后烘干,然后放入石墨模具中进行工装;
(4)将步骤(3)中的工装放入真空气压浸渗炉中,抽真空至0.1~50Pa,升温至500~800℃,将熔融的铝合金浇注到工装内,加注气压至0.5~5.0MPa,完成铝合金的真空压力浸渗,得到制备好的激光3D打印碳化硅陶铝复合材料。
CN201910170802.XA 2019-03-07 2019-03-07 一种激光3d打印碳化硅陶铝复合材料及其制备方法 Pending CN111663057A (zh)

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CN115637346A (zh) * 2022-10-21 2023-01-24 中国科学院上海硅酸盐研究所 一种Al/SiC复合材料及其制备方法

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CN114480908A (zh) * 2022-01-30 2022-05-13 华中科技大学 一种高比分功能梯度铝基碳化硅复合材料及其制备方法
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CN115637346A (zh) * 2022-10-21 2023-01-24 中国科学院上海硅酸盐研究所 一种Al/SiC复合材料及其制备方法
CN115637346B (zh) * 2022-10-21 2023-11-10 中国科学院上海硅酸盐研究所 一种Al/SiC复合材料及其制备方法

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Application publication date: 20200915