公开(公告)号：WO1996006881A2

公开(公告)日：1996-03-07

申请号：PCT/US1995011006

申请日：1995-08-29

Applicant: DTM CORPORATION

Inventor： DTM CORPORATION ,  DICKENS, Elmer, Douglas, Jr. ,  LEE, Biing, Lin ,  TAYLOR, Glenn, ALfred ,  MAGISTRO, Angelo, Joseph ,  NG, Hendra ,  McALEA, Kevin, P. ,  FORDERHASE, Paul, F.

IPC: C08J03/12

CPC classification number: C08J3/12 ,  B29C41/003 ,  B29C64/153 ,  B29C67/04 ,  B29C2035/0838 ,  B29K2023/00 ,  B29K2023/06 ,  B29K2023/12 ,  B29K2059/00 ,  B29K2067/006 ,  B29K2077/00 ,  B29K2079/00 ,  B29K2995/0094 ,  B33Y10/00 ,  B33Y70/00 ,  C08J9/24 ,  Y10S521/919 ,  Y10S525/902 ,  Y10T428/249958 ,  Y10T428/249986 ,  Y10T428/252

Abstract: A laser-sinterable powder product has been prepared having unique properties which allow the powder to be sintered in a selective laser sintering machine to form a sintered part which is near-fully dense. For most purposes, the sintered part is indistinguishable from another part having the same dimensions made by isotropically molding the powder. In addition to being freely flowable at a temperature near its softening temperature, a useful powder is disclosed that has a two-tier distribution in which substantially no primary particles have an average diameter greater than 180 mu m, provided further that the number average ratio of particles smaller than 53 mu m is greater than 80 %, the remaining larger particles being in the size range from 53 mu m to 180 mu m. A powder with slow recrystallization rates, as evidenced by non-overlapping endothermic and exothermic peaks in their differential scanning calorimetry characteristics for scan rates of on the order of 10 DEG C to 20 DEG C per minute, will also result in sintered parts that are near-fully dense, with minimal dimensional distortion.

Abstract translation: 已经制备了具有独特性质的激光可烧结粉末产品，其允许粉末在选择性激光烧结机中烧结以形成接近完全致密的烧结部分。 对于大多数目的，烧结部分与通过各向同性地成型粉末制成的具有相同尺寸的另一部件是不可区分的。 除了在接近其软化温度的温度下可自由流动外，还公开了一种有用的粉末，其具有两层分布，其中基本上没有一次颗粒的平均直径大于180μm，条件是， 小于53μm的颗粒大于80％，剩余的较大颗粒的尺寸范围为53μm至180μm。 具有缓慢重结晶速率的粉末，其扫描速率在每分钟10℃到20℃的差示扫描量热法特征中不重叠的吸热和放热峰所证明的也将导致接近的烧结部件 非常密集，尺寸变形最小。

公开(公告)号：WO1996030195A1

公开(公告)日：1996-10-03

申请号：PCT/US1996004335

申请日：1996-03-29

Applicant: DTM CORPORATION

Inventor： DTM CORPORATION ,  McALEA, Kevin, P. ,  FORDERHASE, Paul, F. ,  GANNINGER, Mark, E.

IPC: B29C67/00

CPC classification number: C08K7/20 ,  B29C39/003 ,  B29C41/003 ,  B29C64/153 ,  B33Y10/00 ,  B33Y30/00 ,  B33Y40/00 ,  B33Y70/00

Abstract: A composite powder specially adapted for use in selective laser sintering is disclosed. The composite powder includes a polymer powder dry mixed with a reinforcement powder, where the polymer powder has a melting temperature substantially lower than that of the reinforcement powder. In the case where near-fully dense parts are to be formed, the first constituent powder is preferably a semi-crystalline powder, for example nylon 11, of a composition suitable for forming near-fully dense parts when used unblended in selective laser sintering; if porous parts are desired, the polymer powder is an amorphous powder, such as polycarbonate, polystyrene, acrylates, and styrene/acrylate copolymers. The reinforcement powder is preferably microspheres of glass, preferably coated to enhance wetting and adhesion with the polymer powder when selective laser sintering is performed. Besides improving the stiffness and heat resistance of the part produced, the composite powder widens the process window over that provided by unblended powder, provides improved dimensional accuracy in the part produced, and facilitates rough breakout and smooth finishing of the part produced.

Abstract translation: 公开了一种特别适用于选择性激光烧结的复合粉末。 复合粉末包括与增强粉末混合的聚合物粉末，其中聚合物粉末的熔融温度基本上低于加强粉末的熔融温度。 在要形成近乎完全致密的部分的情况下，当在选择性激光烧结中未掺杂时，第一组分粉末优选为适合于形成近乎致密部分的组合物的半结晶粉末，例如尼龙11; 如果需要多孔部分，聚合物粉末是无定形粉末，例如聚碳酸酯，聚苯乙烯，丙烯酸酯和苯乙烯/丙烯酸酯共聚物。 增强粉末优选是玻璃微球体，优选涂覆以在选择性激光烧结时增强与聚合物粉末的润湿性和粘合性。 除了提高所制造部件的刚度和耐热性之外，复合粉末可以使工艺窗口比非混合粉末加宽，提高了产品尺寸精度，并且可以使产品的粗切断裂和光滑整理。

公开(公告)号：WO1995030503A1

公开(公告)日：1995-11-16

申请号：PCT/US1995005579

申请日：1995-05-05

Applicant: DTM CORPORATION

Inventor： DTM CORPORATION ,  McALEA, Kevin, P. ,  BOOTH, Richard ,  LAKSHMINARAYAN, Uday ,  GIROUARD, Dan

IPC: B22F03/105

CPC classification number: G05B19/4099 ,  B22F1/0059 ,  B22F3/1055 ,  B22F2001/0066 ,  B29C64/153 ,  B33Y70/00 ,  C04B35/634 ,  C04B35/63424 ,  C04B35/64 ,  G05B2219/49018 ,  Y02P10/295 ,  Y02P90/265

Abstract: The composition and use of polymeric binders in fabricating parts by selective laser sintering. The binders are amorphous copolymers of methacrylic acid derivatives and may contain styrene and its derivatives, as well as additives, such as film forming agents and adhesion promoters. The binders are used to coat inorganic particulate substrates to create a powder comprised of the substrate and binder. The binders flow to form an interconnecting polymeric matrix upon the application of sufficient energy from the laser beam in a selective laser sintering process. Parts are thus fabricated by directing laser energy onto layers of the powder applied at a target surface (4) in successive fashion to build up a three-dimensional part comprised of a plurality of such layers. The part may then be subjected to a high temperature annealing process in a reducing environment, whereby the binders are virtually completely removed by thermal depolymerization of the copolymer, leaving an insignificantly small amount of residual ash.

Abstract translation: 通过选择性激光烧结制备部件中聚合物粘合剂的组成和用途。 粘合剂是甲基丙烯酸衍生物的无定形共聚物，并且可以含有苯乙烯及其衍生物，以及添加剂，例如成膜剂和粘合促进剂。 粘合剂用于涂覆无机颗粒基材以产生由基材和粘合剂组成的粉末。 在选择性激光烧结工艺中，从激光束施加足够的能量时，粘结剂流动以形成互连的聚合物基体。 因此通过将激光能量以连续的方式引导到施加在目标表面（4）上的粉末的层上以构建由多个这样的层组成的三维部分来制造部件。 然后可以在还原环境中对该部分进行高温退火处理，由此通过共聚物的热解聚实际上完全除去粘合剂，留下微量少量的残余灰分。