Mix design and rheological properties of magnesium potassium phosphate cement composites based on the 3D printing extrusion system

It is well acknowledged that the of design concrete structures in the severe conditions such as marine environment has more challenges compared with those constructed in normal circumstances. The demand of fast repairing type materials and its utilization has becoming increasingly significant due to the less durability of the concrete under serious service conditions. The combination of rapid hardening cement with 3D printing technology expands a new area of producing repairing materials in severe environment because 3D printing technology has its unique advantages of producing structural members without casting and assembling. The main purpose of the paper is to examine the printability of Magnesium Potassium Phosphate Cement (MKPC) which as a fast repairing material contributed to maintain the concrete structures in any serious environment. By analysing printed specimens produced by different mixing proportion of MKPC powder, an optimal formulation of suitable combination of the MKPC powder was suggested to improve the printability of the applied materials. Furthermore, Water drop penetration behaviour and different particle size of MKPC powder would also influence the degree reaction between KDP and MgO. Finally, a broad of droplet tests were carried out to obtain an optimized printing nozzle with the inner diameter of 0.06mm which could produce one printable layer with width of 0.9mm.

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Experimental study on the effects of the fiber and nano-Fe2O3 on the properties of the magnesium potassium phosphate cement composites

Journal of Materials Research and Technology ◽

10.1016/j.jmrt.2020.10.030 ◽

2020 ◽

Vol 9 (6) ◽

pp. 14307-14320

Author(s):

Hu Feng ◽

Lijun Lv ◽

Yuyang Pang ◽

Zhenyu Wang ◽

Danying Gao ◽

...

Keyword(s):

Experimental Study ◽

Potassium Phosphate ◽

Cement Composites ◽

Magnesium Potassium Phosphate Cement

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Feasibility study on sustainable magnesium potassium phosphate cement paste for 3D printing

Construction and Building Materials ◽

10.1016/j.conbuildmat.2019.05.053 ◽

2019 ◽

Vol 221 ◽

pp. 595-603 ◽

Cited By ~ 17

Author(s):

Yiwei Weng ◽

Shaoqin Ruan ◽

Mingyang Li ◽

Liwu Mo ◽

Cise Unluer ◽

...

Keyword(s):

3D Printing ◽

Feasibility Study ◽

Cement Paste ◽

Potassium Phosphate ◽

Magnesium Potassium Phosphate Cement

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Preparation and characterization of novel environmentally sustainable mortars based on magnesium potassium phosphate cement for additive manufacturing

AIMS Materials Science ◽

10.3934/matersci.2021039 ◽

2021 ◽

Vol 8 (4) ◽

pp. 640-658

Author(s):

Stelladriana Volpe ◽

◽

Andrea Petrella ◽

Valentino Sangiorgio ◽

Michele Notarnicola ◽

...

Keyword(s):

3D Printing ◽

Potassium Phosphate ◽

Lightweight Aggregate ◽

Environmentally Sustainable ◽

Materials Engineering ◽

Recycled Glass ◽

Magnesium Potassium Phosphate Cement ◽

Binder Ratio ◽

Printing Processes ◽

Water To Binder Ratio

<abstract> <p>The "Digital Transition" of the building sector and in particular the concrete 3D printing is profoundly changing building technologies and construction processes. However, the materials engineering is still a challenge for the research of even more effective and performing 3D printable concrete. In this context, we analysed magnesium potassium phosphate cement (MKPC) performance as an innovative cementitious material in terms of sustainability and possibility of its use in extrusion-based 3D concrete printing (3DPC). Starting from common formulations present in literature, we discussed the relationship between water to binder ratio and workability in two different quantities of retarders. Some mix compositions were also prepared by replacing sand with rubber aggregates or glass aggregates with the aim of creating lightweight aggregate-based mortars. In addition, the fly ash (FA), a widely material used (but that will not be available in the next few years), was replaced with silica fume (SF). We found that two formulations (samples 2 and 7) show rheological requirements and compressive strengths at 90 min of respectively about 2 MPa and 3 MPa, which are deemed to be suitable for 3D printing processes. Moreover, in sample 7, the use of the expanded recycled glass as aggregate opens new possibilities for reducing the carbon footprint of the process.</p> </abstract>

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Effect of Waste Glass on the Properties and Microstructure of Magnesium Potassium Phosphate Cement

Materials ◽

10.3390/ma14082073 ◽

2021 ◽

Vol 14 (8) ◽

pp. 2073

Author(s):

Qiubai Deng ◽

Zhenyu Lai ◽

Rui Xiao ◽

Jie Wu ◽

Mengliang Liu ◽

...

Keyword(s):

Compressive Strength ◽

Glass Powder ◽

Setting Time ◽

Potassium Phosphate ◽

Heat Of Hydration ◽

Waste Glass ◽

Hydration Heat ◽

Magnesium Potassium Phosphate Cement ◽

The Matrix ◽

Powder Content

Waste glass is a bulk solid waste, and its utilization is of great consequence for environmental protection; the application of waste glass to magnesium phosphate cement can also play a prominent role in its recycling. The purpose of this study is to evaluate the effect of glass powder (GP) on the mechanical and working properties of magnesium potassium phosphate cement (MKPC). Moreover, a 40mm × 40mm × 40mm mold was used in this experiment, the workability, setting time, strength, hydration heat release, porosity, and microstructure of the specimens were evaluated. The results indicated that the addition of glass powder prolonged the setting time of MKPC, reduced the workability of the matrix, and effectively lowered the hydration heat of the MKPC. Compared to an M/P ratio (MgO/KH2PO4 mass ratio) of 1:1, the workability of the MKPC with M/P ratios of 2:1 and 3:1 was reduced by 1% and 2.1%, respectively, and the peak hydration temperatures were reduced by 0.5% and 14.6%, respectively. The compressive strength of MKPC increased with an increase in the glass powder content at the M/P ratio of 1:1, and the addition of glass powder reduced the porosity of the matrix, effectively increased the yield of struvite-K, and affected the morphology of the hydration products. With an increase in the M/P ratio, the struvite-K content decreased, many tiny pores were more prevalent on the surface of the matrix, and the bonding integrity between the MKPC was weakened, thereby reducing the compressive strength of the matrix. At less than 40 wt.% glass powder content, the performance of MKPC improved at an M/P ratio of 1:1. In general, the addition of glass powders improved the mechanical properties of MKPC and reduced the heat of hydration.

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Enhancing the mechanical properties and cytocompatibility of magnesium potassium phosphate cement by incorporating oxygen-carboxymethyl chitosan

Regenerative Biomaterials ◽

10.1093/rb/rbaa048 ◽

2020 ◽

Author(s):

Changtian Gong ◽

Shuo Fang ◽

Kezhou Xia ◽

Jingteng Chen ◽

Liangyu Guo ◽

...

Keyword(s):

Mechanical Properties ◽

Compressive Strength ◽

Physicochemical Properties ◽

Bone Cement ◽

Ph Value ◽

Setting Time ◽

Potassium Phosphate ◽

Carboxymethyl Chitosan ◽

Bioactive Substances ◽

Magnesium Potassium Phosphate Cement

Abstract Incorporating bioactive substances into synthetic bioceramic scaffolds is challenging. In this work, oxygen-carboxymethyl chitosan (O-CMC), a natural biopolymer that is nontoxic, biodegradable and biocompatible, was introduced into magnesium potassium phosphate cement (K-struvite) to enhance its mechanical properties and cytocompatibility. This study aimed to develop O-CMC/magnesium potassium phosphate composite bone cement (OMPC), thereby combining the optimum bioactivity of O-CMC with the extraordinary self-setting properties and mechanical intensity of the K-struvite. Our results indicated that O-CMC incorporation increased the compressive strength and setting time of K-struvite and decreased its porosity and pH value. Furthermore, OMPC scaffolds remarkably improved the proliferation, adhesion and osteogenesis related differentiation of MC3T3-E1 cells. Therefore, O-CMC introduced suitable physicochemical properties to K-struvite and enhanced its cytocompatibility for use in bone regeneration.

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Effect of Heavy Metals and Leaching Toxicity of Magnesium Potassium Phosphate Cement

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.117-119.1080 ◽

2011 ◽

Vol 117-119 ◽

pp. 1080-1083 ◽

Cited By ~ 5

Author(s):

Bao Guo Ma ◽

Jing Ran Wang ◽

Xiang Guo Li

Keyword(s):

Heavy Metals ◽

Cement Hydration ◽

Potassium Phosphate ◽

National Standard ◽

Magnesium Phosphate ◽

Toxicity Tests ◽

Hydration Products ◽

Obvious Effect ◽

Leaching Toxicity ◽

Magnesium Potassium Phosphate Cement

Solidiﬁcation / stabilization (S/S) is a popular method for treating solid wastes containing heavy metals. In recent years, it shows positive results of magnesium potassium phosphate cement as stabilizing agent. In the work, the influence of heavy metal Cu、Zn and Pb on magnesium phosphate cement and the leaching behavior of magnesium phosphate cement were studied. Two proportions of cements were employed with hard burned magnesia and potassium phosphate. The hydration products were analyzed by XRD showing that: Cu、Zn and Pb would not take on obvious effect during magnesium phosphate cement hydration process. Leaching toxicity tests showed that: Cu、Zn and Pb were immobilized within cement hydration products through physical fixation, adsorption mechanisms, and the results were far lower than that of the National Standard in China.

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