论文部分内容阅读
几乎所有水声发射器和水听器都采用聚合材料封装。这些覆盖层可使声波穿过时无明显反射、损耗或失真,还可保护水声传感器及电子设备免受物理损坏和海水侵蚀。具有优越声学性能的材料应具有以下主要参数指标:⑴密度和声速接近海水;⑵低机械损耗角正切;⑶中到高剪切损耗角正切;⑷低剪切储能模量;⑸泊松比接近0.50;⑹在研究频率和研究温度内无显著聚合物变化。Division Newport的海军水下作战中心(NUWC)于近期合成了一种新的聚氨酯脲弹性体,用作传感器和水听器的密封材料。这种NUWC XP-1材料,利用异氰酸甲苯酯/聚醚多元醇作基料(分子量约为1500),DMTDA作交联剂或硫化剂。NUWC XP-1在室温下硫化一整夜,达到邵尔A硬度75度。在室温下,XP-1R的声速与海水的非常接近,25℃时的声阻抗为1.71×106瑞耳。NUWC XP-1的水下玻璃化转化温度为-31℃,其动态力学性能使其成为近乎理想的水下传感器/水听器密封材料。将其与几种常用的商业性聚氨酯密封材料比较后(例如中华人民共和国与德索托联合生产的PR-1547、PR-1592;Cyte公司生产的Conathane EN-7)得出结论,NUWC XP-1的性能等于或好于几乎所有能有效密封声学设备和传感器的材料。本产品给行业带来的特殊利益在于NUWC XP-1的化学配方由美国海军控制,且该材料由基本原材料制成,因此相比许多其他商业产品来说,它在未来的使用更广。
Almost all acoustic emitters and hydrophone are packaged in polymeric materials. These coatings provide no significant reflection, loss or distortion when passing through the sound waves and also protect the acoustic sensors and electronics from physical damage and seawater erosion. Materials with superior acoustic performance should have the following key parameters: (1) density and sound velocity close to seawater; (2) low mechanical loss tangent; (3) medium to high shear loss tangent; (4) low shear storage modulus; (5) Poisson’s Ratio Close to 0.50; 无 No significant polymer change at study frequency and study temperature. Division Newport’s Naval Underwater Operations Center (NUWC) recently synthesized a new polyurethane urea elastomer for use as a sensor and hydrophone sealing material. This NUWC XP-1 material, using toluene / polyether polyisocyanate as a base (molecular weight of about 1500), DMTDA as a cross-linking agent or curing agent. NUWC XP-1 is cured overnight at room temperature to a Shore A hardness of 75 degrees. At room temperature, XP-1R sound speed and sea water is very close to the acoustic impedance at 25 ℃ 1.71 × 106Rui. The underwater glass transition temperature of NUWC XP-1 is -31 ° C and its dynamic mechanical properties make it an ideal underwater sensor / hydrophone sealing material. After comparing it with several commonly used commercially available polyurethane sealants (eg, PR-1547, PR-1592, jointly produced by the People’s Republic of China and De Soto, and Conathane EN-7, manufactured by Cyte), it was concluded that NUWC XP- 1 is equal to or better than almost any material that effectively seals acoustic equipment and sensors. The special benefit that this product brings to the industry is that NUWC XP-1’s chemical formula is controlled by the U.S. Navy and made from basic raw materials, making it more widely used in the future than many other commercial products.