CN112374884B - 一种高比重钨合金烧结用承烧板及其制备方法 - Google Patents
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- 238000005245 sintering Methods 0.000 title claims abstract description 30
- 229910001080 W alloy Inorganic materials 0.000 title claims abstract description 25
- 238000002360 preparation method Methods 0.000 title claims abstract description 9
- 238000001035 drying Methods 0.000 claims abstract description 28
- 239000000463 material Substances 0.000 claims abstract description 21
- TZCXTZWJZNENPQ-UHFFFAOYSA-L barium sulfate Chemical compound [Ba+2].[O-]S([O-])(=O)=O TZCXTZWJZNENPQ-UHFFFAOYSA-L 0.000 claims abstract description 20
- 230000005484 gravity Effects 0.000 claims abstract description 19
- 229910021523 barium zirconate Inorganic materials 0.000 claims abstract description 18
- DQBAOWPVHRWLJC-UHFFFAOYSA-N barium(2+);dioxido(oxo)zirconium Chemical compound [Ba+2].[O-][Zr]([O-])=O DQBAOWPVHRWLJC-UHFFFAOYSA-N 0.000 claims abstract description 18
- 235000015895 biscuits Nutrition 0.000 claims abstract description 18
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- 238000005485 electric heating Methods 0.000 claims abstract description 6
- 238000000034 method Methods 0.000 claims abstract description 6
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- 239000007767 bonding agent Substances 0.000 claims abstract description 4
- RVTZCBVAJQQJTK-UHFFFAOYSA-N oxygen(2-);zirconium(4+) Chemical compound [O-2].[O-2].[Zr+4] RVTZCBVAJQQJTK-UHFFFAOYSA-N 0.000 claims abstract description 3
- 229910001928 zirconium oxide Inorganic materials 0.000 claims abstract description 3
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 claims description 18
- QVQLCTNNEUAWMS-UHFFFAOYSA-N barium oxide Chemical compound [Ba]=O QVQLCTNNEUAWMS-UHFFFAOYSA-N 0.000 claims description 8
- 239000011230 binding agent Substances 0.000 claims description 4
- 230000006641 stabilisation Effects 0.000 claims description 4
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- 239000011347 resin Substances 0.000 claims description 3
- 229920005989 resin Polymers 0.000 claims description 3
- 229910001233 yttria-stabilized zirconia Inorganic materials 0.000 claims description 3
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- 239000004372 Polyvinyl alcohol Substances 0.000 description 4
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- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
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- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
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- 229910052742 iron Inorganic materials 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229910052863 mullite Inorganic materials 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 231100000252 nontoxic Toxicity 0.000 description 1
- 230000003000 nontoxic effect Effects 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 238000004663 powder metallurgy Methods 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 1
- 229910052721 tungsten Inorganic materials 0.000 description 1
- 239000010937 tungsten Substances 0.000 description 1
- 238000009736 wetting Methods 0.000 description 1
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Abstract
本发明公开了一种高比重钨合金烧结用承烧板及其制备方法，包括：（1）将原料及结合剂放入高速混炼机中混合均匀，原料包括粒度≤80目的电熔锆酸钡50%～65%、粒度≤325目的电熔锆酸钡20～30%、粒度≤1000目的电熔氧化锆10～20%、硫酸钡微粉3～6%，结合剂占原料的重量百分含量为4～6%；（2）将混合均匀的物料按素坯单个重量称重后倒入模具中成型；（3）将成型后的素坯自然干燥1～2天，然后入电加热干燥窑在150℃～200℃下进行24～30小时烘干；（4）在1680℃～1750℃温度下烧制6～10小时，得到高比重钨合金烧结用承烧板制品。本发明很好的解决钨合金粘连问题，并提高了承烧板的抗热震性。
Description
技术领域
本发明涉及一种高比重钨合金烧结用承烧板及其制备方法。
背景技术
高比重钨合金具有密度大、强度和硬度高、导电性好、热膨胀系数低、抗腐蚀和抗氧化性高等优点，常用作穿甲弹材料、屏蔽材料和触点材料，广泛应用于军工、航天、医疗等领域。钨的熔点高、难以烧结，需要加入少量Ni、Fe和Cu等合金元素，合金元素在较低温度下熔化形成液相，实现钨合金的烧结致密化。对于不锈钢粉末冶金产品，烧结时经常使用刚玉-莫来石质和99氧化铝质承烧板，但由于高比重钨合金烧结过程中金属熔融相的存在，烧结时易与现有材质的承烧板发生粘连，从而影响钨合金的正常生产。
发明内容
为解决以上技术问题，本发明提供一种高比重钨合金烧结用承烧板及其制备方法。
本发明提供的一种高比重钨合金烧结用承烧板的制备方法，包括如下步骤：
（1）混料：将原料及结合剂放入高速混炼机中混合均匀，所述原料包括如下重量百分比的组分：粒度≤80目的电熔锆酸钡50%～65%，粒度≤325目的电熔锆酸钡20～30%，粒度≤1000目的电熔氧化锆10～20%，硫酸钡微粉3～6%，所述结合剂占原料的重量百分含量为4～6%；
（2）成型：将混合均匀的物料按素坯单个重量称重后倒入模具中成型；
（3）烘干：将成型后的素坯自然干燥1～2天，然后入电加热干燥窑在150℃～200℃下进行24～30小时烘干；
（4）烧成：烘干后，在1680℃～1750℃温度下烧制6～10小时，得到高比重钨合金烧结用承烧板制品。
进一步地，所述电熔锆酸钡中氧化钡含量≥50%。
进一步地，所述电熔氧化锆为氧化钇稳定氧化锆，稳定化率为50%～85%。
进一步地，所述硫酸钡微粉 D50≤5um。
进一步地，所述结合剂为PVA、水溶性树脂中的一种。
本发明还提供了一种采用上述制备方法制备的高比重钨合金烧结用承烧板。
本发明的有益效果在于：
（1）本发明的承烧板以电熔锆酸钡为主要原料，电熔锆酸钡具有熔点高、化学性质稳定、难以被金属熔体润湿的优点，可以很好的解决钨合金粘连问题；
（2）本发明采用无毒的硫酸钡粉体作为促烧剂，在高温下分解成高活性的氧化钡，与氧化锆原位反应生产锆酸钡，促进烧结；
（3）本发明在粉料中加入粒度≤1000目的稳定化率在50%～85%的电熔氧化锆，利用其中单斜氧化锆相变体积效应在承烧板内部造成适量的显微裂纹，提高了承烧板的抗热震性。
具体实施方式
为了使本发明的目的、技术方案及优点更加清楚明白，以下结合实施例，对本发明进行进一步详细说明。应当理解，此处所描述的具体实施例仅仅用以解释本发明，并不用于限定本发明。
为避免重复，先将本具体实施方式所采用的的原料统一描述如下，实施例中不再赘述：
所述电熔锆酸钡中氧化钡含量≥50%；所述电熔氧化锆为氧化钇稳定氧化锆，稳定化率为50%～85%；所述硫酸钡微粉 D50≤5um。
实施例1
（1）混料：将重量百分比为50%的粒度≤80目的电熔锆酸钡，30%的粒度≤325目的电熔锆酸钡，14%的粒度≤1000目的电熔氧化锆，6%的硫酸钡微粉，以及占原料的重量百分含量为5%的PVA放入高速混炼机中混合均匀；
（2）成型：将混合均匀的物料按素坯单个重量称重后倒入模具中成型；
（3）烘干：将成型后的素坯自然干燥1天，然后入电加热干燥窑在150℃下进行30小时烘干；
（4）烧成：烘干后，在1680℃温度下烧制10小时，得到高比重钨合金烧结用承烧板制品。
实施例2
（1）混料：将重量百分比为55%的粒度≤80目的电熔锆酸钡，25%的粒度≤325目电熔锆酸钡，17%的粒度≤1000目的电熔氧化锆，3%的硫酸钡微粉，以及占原料的重量百分含量为4%的PVA放入高速混炼机中混合均匀，
（2）成型：将混合均匀的物料按素坯单个重量称重后倒入模具中成型；
（3）烘干：将成型后的素坯自然干燥1天，然后入电加热干燥窑在200℃下进行24小时烘干；
（4）烧成：烘干后，在1700℃温度下烧制8小时，得到高比重钨合金烧结用承烧板制品。
实施例3
（1）混料：将重量百分比为65%的粒度≤80目的电熔锆酸钡，20%的粒度≤325目的电熔锆酸钡，10%的粒度≤1000目的电熔氧化锆，5%的硫酸钡微粉，以及占原料的重量百分含量为4%的水溶性树脂放入高速混炼机中混合均匀，
（2）成型：将混合均匀的物料按素坯单个重量称重后倒入模具中成型；
（3）烘干：将成型后的素坯自然干燥2天，然后入电加热干燥窑在150℃下进行24小时烘干；
（4）烧成：烘干后，在1750℃温度下烧制6小时，得到高比重钨合金烧结用承烧板制品。
以上所述仅为本发明的较佳实施例而已，并不用以限制本发明，凡在本发明的精神和原则之内所作的任何修改、等同替换和改进等，均应包含在本发明的保护范围之内。
Claims (6)
1.一种高比重钨合金烧结用承烧板的制备方法，其特征在于，包括如下步骤：
（1）混料：将原料及结合剂放入高速混炼机中混合均匀，所述原料包括如下重量百分比的组分：粒度≤80目的电熔锆酸钡50%～65%，粒度≤325目的电熔锆酸钡20～30%，粒度≤1000目的电熔氧化锆10～20%，硫酸钡微粉3～6%，所述结合剂占原料的重量百分含量为4～6%；
（2）成型：将混合均匀的物料按素坯单个重量称重后倒入模具中成型；
（3）烘干：将成型后的素坯自然干燥1～2天，然后入电加热干燥窑在150℃～200℃下进行24～30小时烘干；
（4）烧成：烘干后，在1680℃～1750℃温度下烧制6～10小时，得到高比重钨合金烧结用承烧板制品。
2.如权利要求1所述的一种高比重钨合金烧结用承烧板的制备方法，其特征在于：所述电熔锆酸钡中氧化钡含量≥50%。
3.如权利要求1所述的一种高比重钨合金烧结用承烧板的制备方法，其特征在于：所述电熔氧化锆为氧化钇稳定氧化锆，稳定化率为50%～85%。
4. 如权利要求1所述的一种高比重钨合金烧结用承烧板的制备方法，其特征在于：所述硫酸钡微粉 D50≤5um。
5.如权利要求1所述的一种高比重钨合金烧结用承烧板的制备方法，其特征在于：所述结合剂为PVA、水溶性树脂中的一种。
6.采用权利要求1-5任意一项所述制备方法制备的高比重钨合金烧结用承烧板。
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